Any of these: 1, 3, 13, 17, 47
13. What type of AUs are your favorites? Give a general description.
I love college AUs. There should be a million more of those. You have all the fun of characters acting like trash, with the added fun of (more) drinking and you know, legal consent and all of that. I'm also a big fan of AUs that alter timelines--for example, a Pride and Prejudice fic where Darcy asks Lizzy to marry him again before Lydia runs off with Wickham. That kind of thing.
17. Name a fic that made you laugh a lot.
"The dog days are over (because the cat's out now too)" by coalitiongirl. Something about the lines "Archie is telling you bald-faced lies" and "Regina didn’t ask for any of this, she’d just wanted some vengeance on her enemies and absolute reign over a sleepy town in Maine" just kills me every time. I adore secret-softie Regina acting long suffering while surrounded by shenanigans, I don't know.
47. If you had to introduce someone to fanfiction with a few fics, which would you suggest?
For OUaT I'd suggest "Like Whiskey", a CS fic, to the type of general audience member who isn't familiar with fanfiction. Since it's a pairing they'd be familiar with from the show itself, that explores what fanfiction can do while still remaining mostly in the realm of canon constraints. And also it's not terribly long. And then I'd move to something accessible and trope-y like "a million tiny little things" because tropes are the backbone of so many fanfictions.
After that the sky's the limit, really. Although smut can be a dark and dangerous place.