I'm worried some are bad from a crash/break point of view ... if they are all just perf tradeoffs then a big "fast or battery" button (slider perhaps) could cover it. And save the settings separately according to whether I'm on AC.
Powertop mostly just makes me feel that my OS could have had good battery life but doesn't.
A doc blurb about the tradeoff for each toggle might go a long way though. Or if all of them have a "slowdown" worst case, one global blurb explaining that they're all safe but may cause performance decrease.