Few nitpicks from me:
Cho Chang, skin color is way off
Draco Malfoy, he shouldn't have the snitch (well, maybe he did succeed in one of the off-screen matches, but neither books nor movies mention it). I think they should have gone with normal Slytherin outfit and maybe an arm cast from when he was 'injured' by Buckbeak? Or his suit from HBP.
Luna Lovegood, that skirt is unnecessary, I don't even remember her wearing something like this in the movies
that mandrake is weird, looks like it has a frown printed on top of a smile.
The rest is pretty much perfect. I'll try to get all of them, obviously. Good thing my nearest LEGO shop has an employee that's really good at feeling bags, he was of massive help when I wanted few Batman CMFs I didn't have yet. Hopefully he'll be there when I'll have time to visit