Harry and Draco end up in Hufflepuff—prefect Cedric Diggory will not take Draco's "pureblood" crap. Harry and Draco both end up terrified of him and apparently bonded over that. Neville and Hermione are in Slytherin, and Neville pretends she's a relative of his to keep her alive. Pansy, Pavarti, and Ron get Ravenclaw—Pansy is totally on board with that, with Fashion!. Hannah, Crabbe, and Goyle get Gryffindor—Hannah civilizes the boys quickly and they become her best pals.
Qudditch? Harry and Draco are Hufflepuff chasers, Ron's a Ravenclaw keeper, and Hannah is the Gryffindor seeker. Hermione still doesn't see what the big deal is about the sport.
And the group gets to the Stone before Christmas first year, pretty much because Draco felt like it.
Everyone feels pretty in character—Ron's only being a prat at the start because he's frustrated about living up to being in Ravenclaw and doesn't know Harry well and therefore thinks he's a glory-hound, Draco is snarky and rude as ever (he eats all of Harry's chocolates when Harry is in the hospital wing and thinks he deserves it for being "dragged into" the stone mess), Hermione becomes scarily more
organized and Pansy is fashionable and cunning. Harry sometimes just seems to be going with it, but still has his 'do-right' traits.
And then Ginny ends up in Slytherin and does not take Marcus Flint's bull, verbally smacking him down at the welcome feast. She's planning to go for Quidditch too, once she has a broom.
There are however, moment of dark humor, such as Draco briefly contemplating killing his father when he finds out his dad was behind the Chamber of Secrets...actually, anything having to do with Lucius Malfoy ends up being darker humor. Pansy and Draco both get the veil lifted from their eyes by third year and it is not pretty.
On the whole though...made of funny!