I gave some more thought about the possiblity of using SAGA cards for Supercrew, and I came to a conclusion- they should not replace the dice, but merely act as the Hero Points. The dice mechanic itself is too simple and elegant to mess with.
Redforce, you are the famous off author of some of the best RISUS supers options ever! You can just take what you want from us mere mortals! But please, steal away. They dont have to be powers. I've been running "atomic horror" type 50s-movies game using Supercrew rules, letting the players define themselves with a handful of aspects and they're off. it's a nice easy way to get things moving.