I also don't buy fics that characterize Al as this shy wallflower type who never speaks up and lets James bully him. It was the house, not Al, Harry was worried about when James offered to share a room with him. Maybe Al is quieter, less rambunctious, maybe a bit more sensitive than James, but I think he's capable of giving as good as he gets.
I've noticed this in a lot of Al fics. They always portray him as this shy kid and while I think he's more sensitive than James and probably nicer overall, I don't think he's
that shy. I think the line Harry says about them sharing a room often gets ignored, but I take that as proof that Al himself can be quite the handful if he wants to be.
Fanfic Rants