You didn't talk about MODS! So I will.
Basically if you look at the mod list in stepmania, that's what you get in ITG. The difference is that unlike the default stepmania theme, in ITG you can have multiple mods selected from the same line. So you can basically do what I call mod stacking to get some absolutely crazy results :
Edit : Unfortunate timing on my part, I took too long to make my post
