I am an old lady that loves reading. I can't write worth a damn but I am a decent critic and picky about spelling, grammar and correct word choices (no "there" instead of "their", "Snack instead of Shack").
I primarily read Harry potter but love NCIS, Buffy, and Star Wars almost as much.
My preferences in stories: Stories where people get what is really coming to them and where bad behavior is not rewarded. This means, for example, Harry potter stories where either Dumbledore is actively shown for the Evil manipulator he is in JKR's world or He realizes what he is doing and become the Teacher/Mentor that he was supposed to be doing.
It is my tastes but I don't read male/male slash and only female/female when part of a three-way or more relationship and even then, I prefer fade to black, not lemons. I will skip over the lemon scenes for a good plot. When I was in my 20's, it was interesting to read, but that was decades ago and tastes change. I don't mind those that write such scenes as long as they keep it out of their summaries that you see while looking at lists of stories.
Views on Canon Characters
Luna Lovegood: I won't say much, just that she is my favorite character. I love her quirkiness, her brains and her unusual way to look on the world that bullies her. She is the creative right brain character to Hermione's left brain and genius in her own right. I know what it feels like to be bullied so I can relate to her and her keeping so good despite it.
Draco Malfoy: He is a bully and should be smacked down hard and punished. He should be taught that actions have consequences and reactions. He should learn from them or get hurt or taken out. I can't see a Malfoy/Granger romance as believable in any way shape or form. I like the stories that do sometime redeem him by either confusing him and the converting him, revealing him as abused to break him out of cycle or he grows from being shown consequences as much as ones with him as villain that gets beaten but I hate him getting 1001 chances. To make him anything other than villian even one pressured by circumstance (and perhaps family love, even many of the most evil men in history loved their mothers and their pets) is something of fanfiction, not of canon.
Hermione Granger: I really love her as a character, she is my second favorite character in the story provided she gets smacked with a clue bat about her know-it-all behavior to tone it down to become a friend and it only flares occasionally to create small tensions. I like the way she can be changed to become friend or villain but makes a great support and help. Her obsessive obediance to authority that takes years to overcome really should be cured a lot earlier. Definition of madness is doing the same thing over and over and expecting different results and she is that way with trusting authority just because they are authority. She is great with logic but horrible with creativity (all left brain and little right) and I like when this cured in a story.
Ron Weasley: I hate Ron Weasley. I was so happy when I learned that JKR in an interview admitted that she was wrong to pair Ron with Hermione. He is a Prat and bigot as bad Draco with his blind hatred of Slytherins, his betrayals of friendships and immaturity. He insulted Hermione such that he should have been badly punished book 1, he was reason for the midnight duel book 1, he turned his back on Harry multiple times, his jealousy and insecurities driving him. He does not show good judgement even once in the book and is the naysayer and insulter to drive others away. He is a minor villain and obstacle to overcome. He is like those celebrity stalker that want to be with the celebrity because of their fame and that fame washing over them by association. He really never seems a true friend to anyone but himself. He wants the fame and attention and sucks up to get a deprived harry to accept him and let him get in on the adventures. When going gets tough, or he is not center of attention, he gets going.
I like stories where he reforms and learns or he becomes a outright villain because I don't like that despite stabs in the back over and over with him being forgiven and accepted back. I guess if you are desperate for help you accept what you can but I don't really like it. To make him tolerable, he really needs to be given something that separates him from his brothers and harry and shows him in a spotlight of his own which is hard because harry is a practical magic genius
Molly Weasley: She was supposed to be a maternal influence in Harry potter, she was more harpy and harridan. She is the overbearing, pushy, opinionated witch that everyone wants to get away. She exists as authority figure to get around and issuer of punishments. Her howlers are abuse at minimum and I accept why all her children turn away from her. The fact that she tries to claim authority in Sirius's house in book 5 over the owner of the house was unacceptable and 3 weeks in book 2, 2 days in book 3, two weeks in book 4 does not make her Harry's Mother and give her right to abuse him. I don't like that JKR had her kill Bellatrix because she was threatening Ginny considering Bellatrix should have gone to Neville or if Neville was considered enough because of Nagini and facing Riddle, then Hermione for the torture. (JKR just had to give a long term major character someone to win over but Bella was not right choice unless you wanted Cruel Harpy versus Cruel Harpy Battle). Her being evil or poor starts in book 1 where why would someone that had been to the Hogwarts train over 100 times be asking loudly in middle of MUGGLE side about muggles and platform 9 3/4. Either it is a setup that is rigged or she is a bloody idiot and idiot doesn't seem to apply. I accept fanfiction showing her as potion mistress Molly (based on the one line of her using one on Arthur) and villain but she is just as bad as JKR created her without adding anything.
Ginny Weasley: The ultimate fangirl. She is never showed as much of anything but a fangirl in most of the series who stalks without talking most of the way. She gets to date harry in 6th year but even that is mostly glossed over. She is shallow, superficial. There is no depth, no meaning, no real ginny other than the most superficial in canon means she is there just so JKR has someone to eventually give harry because she wanted to force a Ron/Hermione. This lack of depth, lack of showing her true character, lack of substance is why fandom can so easily make her a good person (by adding the depth) or the evil potioneer or gold digger (playing up the fangirl and obsession). Even her time in chamber of secrets shows her nature is so overlooked that no suspects her because no one sees her.
Dumbledore: As JKR wrote him, she might has meant for him to be mentor type but I see him as evil manipulator at worse and total incompetent at best. I am talking about Canon books only not fan fiction abuses like potioning loyalty, magic and ability binds, compulsion/memory charms or stealing from Harry's vault. Many Fan fiction seems to feel that they have to make him 10x to 100x worse. Evil prospers when good does nothing but he is not doing nothing but actively seems to be doing evil with callous disregard for life and justifying it as good.
Let's look at what he does in the books:
Book 1: He kidnaps harry and puts him into abusive environment and never checks on him and yet when there is trouble with the letters, he sends Hagrid (mentally deficiency, does not blend with statue of secrecy, opinionated to play up his reputation) to take Harry shopping to keep him ignorant and his actions hidden. He claims magical guardian and yet never saw to Harry's proper education. He is supposedly the most powerful wizard in the world but can't detect Quirrell, hides a major artifact as lure for murderous evil in a school full of children with poor traps. Including a killer three headed dog behind a door that first year alohamora charm can open. He takes a broom to ministry of magic instead of Floo, apparation or portkey which means he is deliberately creating opening for villain to get access. He could have put stone under fidelius in a cabinet in his office. He puts an addictive mirror out for Harry to find and obsess about as part of using him. At end of story he then conceals information from Harry as to why he was targetted as opposed to giving a little comfort or reason for it. He could have said "Voldemort can not let anyone that escaped or defeat him live, it threatens his power." just as easily as he said "You are not old enough". It would have made poorer story but would have shown him in a positive light if he said he had hidden a fake and the real was never in any danger. The adding 170 points to Gryffindor at ending feast (literally equal to 1/3 house had gotten all year among all the members) as abusive and horrible and shows Slytherin why being good isn't worth anything. It undermines the house point system as bad as Snape. He doesn't actually teach anyone anything. Then at the end of the year, he just bluntly sends Harry back to Torture with Dursley's without even ask Why Harry doesn't want to go back.
This is not a good man
Book 2: He hires Lockhart and can't tell the guy is incompetent. He knows about prior release of Basilisk as he was teacher then. He can't tell what the creature is, he can't sense the evil of the dairy in the school wards, he can't figure out clues of the killing roosters or spiders leaving school and doesn't close school and bring in experts when first student is petrified. He choose to have school wait full YEAR until school grown mandrakes mature as oppose to seeking them elsewhere. If Fawkes could get to chamber, so could Dumbledore so why was only the hat sent. And again, he undermines house point system with points equal 1/2 of a full year for entire house awarded at end. He then sends the Harry back to Abuse. Hell, if he is monitoring Harry, he should have intervened and dealt with the Dobby issue and warning on record but evil manipulator needed that leverage for future.
Another book where he is no help, no teaching, and perhaps impediment.
Book 3: It comes out that the Chief Judge placed Harry in the abusive home while his rightful guardian was still out. It was done before longbottom were incapacitated or Sirius was arrested. He as chief judge then ALLOWED one of his major allies and members of his order to be put in jail without a trial (abandoning loyalty, hard work, doing what is right, and his responsibilities and duties) or even proper questioning. He leaves paths into the school that he knows about unwatched and unchecked to allow a supposed murderer into the school (Dumbledore arranged Whomping willow route to shrieking shack for Remus). He tells children to Alter TIME rather than step up to his responsibilities as chief judge and of course arranges for Harry to be sent back to abuse at the end of summer. This helps him continue his grooming harry for sacrifice.
Book 4: His long time friend and order of the phoenix member is not noticed as being different? He only puts age line to guard cup when even most idiots can think of having 6th or 7th year put the name in the cup for them. Crouch senior was imperioused during early cup meeting and he couldn't recognize the signs of imperious after all his years and yet Harry could right away in maze. He never considers that death eater might be involved and never even considers Moody as possible when having reason for entry into tournement investigated. He is supposed to be genius and doesn't think of 2 people to investigate and checking them for imperious so that they could check and possible suspect couldn't control it. I think he knew exactly what was going on and was trolling for bait, sacrificing his pawns yet again as tools in his inhumanity.
Book 6: He demanded Snape who is reforming to kill him. Only in Machievellian plotting and assumption that Voldemort would successfully take over would make this plotting acceptable. He wants to destroy the restored humanity (not that there is much) of Snape by forcing him into another murder or euthanasia while sparing Draco who to this point has not shown even a drop of remorse.
Later books are even worst but as someone that knew "I was sending you for 10 Long dark years", he is evil. At best he is incompetent obstacle, at worse he is as bad a dark lord as Voldemort. I wonder when Snape's birthday is and whether Eileen Price defied dumbledore 3 times (Snape could have been child of prophecy when he killed dumbledore at end of book 6. Might be fun to see that written into story, july birthday snape.)
Consider the way he runs his order of the phoenix. No dissent to his leadership is allowed. No, he doesn't use crucio and pain to punish but he has created cult of personality that his "disappointment" and "You know I know best" worked well enough on fanatics and people of good morals. He keeps people prisoner (Sirius in his own house, Harry at Privet Drive as blood wards would keep away death eaters or are worthless which means guards are just to keep Harry confined). A good person does not see the truth as a "beautiful and dangerous thing" to hide.
Let even go further, he knew that voldemort was not dead because of Snape and dark mark that was faded but not gone and he sat on his behind for 10 years doing NOTHING to wait for a pawn to do the work for him. He had the books about Horcrux, why did he wait until he had proof at end of harry's 2nd year? Why didn't he get some unspeakables or order of phoenix and go deal with issue. Why did he allow Sirius go to jail without trial instead of letting him raise Harry somewhere private (announce to public he is hidden away). He could then have had Sirius, Remus and Snape with him to deal with inferi and locket horcrux almost immediately. He could have destroyed Riddle's reputation right from the start by revealing he was a half blood (powerful but still half blood to blood purists).
The absolute worst is that he is raising and grooming Harry to be a Martyr. When he says that Harry's greatest power that voldemort doesn't have is love. He is talking in terms of Christ who per christianity so loved his fellow man that he died for their sins to redeem them. Note though, Christian Christ voluntarily and willingly died and sacrificed HIMSELF (if you are of that belief and religion) while Dumbledore is sacrificing others over and over and demanding that sacrifice of Harry. Good can die because they are good, evil has to survive for the slimmest chance they can be HIS definition of good. This means the person of the GREATEST GOOD has to die try to redeem evil with no backup if evil is not stopped.
He is the chess master that thinks because he knows more, he can do as he likes. The ONLY good thing he does anywhere in any book in the books is deal with one of the Horocrux of his Rival for power (He attempts a second but only gets a fake). He is so blinded by his lust for a certain power, it puts him on path to death and he has to put burden of making his death suit his timing on another (burdening the soul of Snape to commit murder). I will allow possibility of delusional and narcissistic that if it doesn't fit his world view it can't be happening (families love each other so no way there could be abuse). "Inconceivable" from princess bride is example like this but that was also a villian character. That still only covers somethings.
A number of my friends are adamant he is leader of light. I can't see him that in more than just title, he is grey and dark that uses and abuses people. Perhaps he is just the most fatally flawed neutral character but I can't see him as anything other than one of the three most evil people in the books with Umbridge and Voldemort. He might be the worst because the others are obviously Evil (umbridge), evil/Insane voldement (megamaniacal, psychopathic, narcissitic sadist) while he is hiding as the good Shepard. I can enjoy a fanfiction that has him as the true gandalf, mentor and guide character but in canon he is almost as bad as the worst fanfiction portrayals. The fanfictions just give him more scenes to make it public, blatant and obvious that he is evil vs the subtle evil (controls that are not seen as controls) of JKR.
At best, He is a tyrant per CS lewis's quote: "Of all tyrannies, a tyranny sincerely exercised for the good of its victims may be the most oppressive. It would be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated; but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." but I think this is overly generous and too mild.