By default, OVA doesn't limit character abilities, but it does suggest several limitation methods (p21). Which method(s) work well for high-powered characters? I’d like to run games with fantastic settings, superhuman and supernatural characters, etc. At the same time, I want to present the PCs with interesting challenges, and I’d like them to be on equal footing with each other. That's my goal for imposing limits.
There aren’t many examples given for Power Ceiling and Scaled Cost, so I don’t know where to set the numbers if I use them. I don’t want to saddle PCs with so few levels that they wind up average Joes instead of fantastic heroes. I don’t want to give them so many that I struggle to challenge them, either.
I’m also uncertain about Base Zero. Most of the sample characters comply with it, and many of them have 20+ points of abilities, thus 15+ points of weaknesses. I’m concerned that it might be difficult to keep track of so many weaknesses during play, that they won’t all get utilized, or that players won’t enjoy RPing that many flaws.