A couple of suggestions:

Firstly, I wanted to download FFR, but its down at the mo. So, I get the first simulator i see. This Stepmania its pretty good.
What I noticed was freeze arrows, where you would hold down an arrow for a certain amount of time, which i though was pretty neat. Also, that DWI creater on this site can make them which is another bonus.

Anyway, the idea is maybe form a hierachial structure for the many songs that will probably come out in future versions.

eg

Dance - Rave
techno
other

Rock - Punk
Industrial
Ska

you know, maybe something to neaten up the choise lists instead of having to clutter the front page?

Thanks