I would absolutely love a black/dark theme. They keyboard is much sexier when dark and I love how the iTunes Store app looks when I browse through TV/movies.
I wish I didn't have to press "ok" after putting my passcode in.
A listing of daily events in calendar instead of dots. That might be something that keeps me from putting iOS 7 on my iPad. I like quickly looking at the month to see what is going on. Dots don't tell me much.