Well, I think decent worldbuilding is a must. Regardless if you're going the route of completely demolishing and rebuilding the wizarding world from scratch or simply building on the blocks that Rowling set in place, it has to be there in some form or another. Naturally, too many people confuse worldbuilding with infodumps and that's how we get all those tedious chapters chock full of information, delivered in the most off-putting ways. It's best when done gradually, bit by bit. No one ever learns everything there is about something in the span of a few chapters, and they shouldn't.

In that same regard, books/school and family libraries should not be the ultimate source of knowledge. Not all knowledge has to be readily or conveniently accessible to anyone in the fic, be they the protagonist or antagonist. Make them work for that knowledge. Make them work and from time to time have them fail in their search.

This ties into another important matter for what I want to read in fanfics: the wonder of magic. I'm talking about real wonder. Something that will leave you with both an impression of just how powerful magic can be and how intrinsically mysterious. Don't quantify everything. Don't try to explain everything with some kind of indisputable explanation. Let there be mystery and genuine awe in the way you write about magic. Let readers wonder in delight as they read about various acts of magic. And of course, don't limit yourself to just wand spells. Go beyond the norm. Go beyond the world of witches and wizards. For fuck's sake, there's sentient magical beings in the world already, but barely anyone taps at the potential they hold. Instead, everything seems to revolve around one train of thought and that's boring.

Next up is decent characterization. Yes, I can understand that children will be children. I'm not demanding, nor am I expecting that they behave as adults. But as the years in your fic pass on, let the characters show that. Other than just changing the Hogwarts syllabus (or the DADA professor) and occasionally bringing up new sorts of magic they learned about in class, let your characters' growth also act as an indicator of time passing by.

You can have one-dimensional antagonists. Nothing wrong with that. Just make sure they're not the focal point of your whole fic, else they'll be easily defeated and even more easily ridiculed and discarded in some kind of pitiful attempt at showing off how powerful, how clever your protagonist is. Hell, one dimensional antagonist is best for the early years. Some little runt (e. g. Malfoy) running his mouth off, trying to pull shit - sure, take care of him easy peasy. Just don't make every single antagonist that follows after the same. The main antagonist (if you have one to begin with) is someone you could possibly see the appeal of - even if you (as the reader) have to step out of your comfort zone for a bit.

 

Depends on the verse but in a general sense I want more of the same. More of the fandom I enjoyed. Alternate takes or in between the scenes are all fine. The characters tend to be the most driving part of it for me. A good piece where two characters interact well tends to more than suffice. Epicness is a bonus but it's so damn rare.

 

What You Leave Behind

The Black Prince

Shadow Of Angmar

No particular order.

 

Canon explored in a different way. I always find it most fascinating when an element is taken out of canon and then gets explored in much more detail. This can be pretty much everything, ranging from the way magic works (Newcomb's "What You Leave Behind") to some particular sentences (the explanation for death being the next great adventure that can be found in "Harry Potter and the Chrysalis" by the Imaginizer) or just a different take on certain events (like Gilderoy Lockhart's first class in "Harry Potter and the Prince of Slytherin" by The Sinister Man, or the completely different petrifications in that story).

To take canon and put a spin on it that no one expected and that still seems plausible is, for me at least, the very best fanfiction can achieve.

Apart from that, I like it when the main protagonist has above-average abilities (who doesn't?). Oh, and Dumbledore has to be one of the good guys. A bit of moral ambiguity is also always welcome.

 

What I want to read is usually what I want to write but haven't yet. Harry Potter and co using magic in a weird, original setting like high concept sci-fi or well considered alternate universes. Harry Potter and co messing with metafiction in a clever way. A good young Dumbledore story. A good old Dumbledore story. More Hannah, Romilda, Cho, Marietta, or even Padma in interesting ways.

 

I'd like to read a well written story about Riddle's time after Borgin and Burkes, during his rise to power and covering the decade he disappeared. Or an AU where Ariana never died, and so Grindelwald and Dumbledore never split and went on to go through with their plans of wizarding dominance.

 

I'm the opposite of Cheddar in that almost all of what I read has some form of romance or shipteasing. I love romance, and let me be clear when I say it doesn't have to be the primary purpose of the fic, it just has to be well done.

Dunno why it's such a big deal for me, but the only way I read stuff without romance is if it's rather spectacular.

 

Much like other people who have already spoken in this thread I love huge AU worlds, a more magical magic system, and canon divergence before Harry Potter.

I find that much of the Harry Poter universe is left up to the reader's imagination, and a good author can capitalize on this. There are so many times and places that you can explore in the Harry Potter Universe that it is actually a bit saddening that most stories are usually just a canon-rehash with small changes. I would love to read about Wizarding Empires, wizards over history, or even a world where there is a larger wizarding population and all muggles know about magic.

This is one of the reasons I love stories like A Long Journey Home. It explored wizards in so many different times and places that it really painted a new light on what Harry Potter lore could be.

Stories like Skitterleap and Harry Potter and the Heartlands of Time taking the story out of Britain is also incredibly interesting.

Another interesting thing is the magic system. There are too many scientific takes on magic trying to break it down and explain each bit piece by piece. It takes much of the wonder and excitement out of Harry Potter. I would love a story that keeps it exciting, interesting, and mysterious.

Other canon divergences are interesting. Some questions could be: What if Grindelwald won? What would happen if other magical races joined together to fight the wizards?

The last thing that I want in a story is war. I would love a huge magical war between various nations, parties, or even continents.

 

I want to read Harry centric time travel of any sort. However a dark Harry traveling to the future would be a nice twist for a change. There was one a couple of years ago called the Star Empire that never got finished that seemed almost one of a kind. It's a pity it was abandoned and taken down.

 

Fics that stay as far as possible from canon plot. So either non-rehashy AUs, or post-Hogwarts stuff.

Also, I want to see the setting being actually utilised and expanded on.

 

What do the earlier books feel like to you? Personally, I've always thought of the first three or four as the three friends investigating things beyond their abilities, getting as much wrong as they do right, but ending up where they need to be. That formula is a lot of fun, but it's hard to find that in fanfiction because so many events are already known if the story sticks too closely to canon. Or are the early books more about the three friends themselves and discovering new facets of the magical world?

Edit: To answer the thread's prompt, a compelling system of magic that isn't concrete but not too vague too allow deus ex machina solutions for everything. Also, plausible power dynamics where Harry doesn't just face universal approval from everyone who isn't a Death Eater. A paranoid, war time environment should see several different interests surface to struggle for control. Even if the war is still nominally two sided, I like factional divisions within the Order, Ministry, or Death Eaters.

 

I feel the same about Voldemort's rebirth. Once he's active again, it's like the entire focus is just on putting him down.

 

A decent HP/PJO crossover.

 

So much this.

 

I really want to read more fics where HP becomes a dark lord without bashing. It woul also help if there was not a super Harry and that kind of scifi stuff.

 

What is a "dark lord" and why should Harry become one?

 

Voldemort... with a beard.