Ok I'm stepping up and taking the pointy stick real fast. Avatar ain't real life. It ain't always going to be logical. It ain't always going to fit in to the four panels you wish it would. Stop trying to force it to.
Now as for personal op-eds on skill caps. Quad Digit OR's, DR's, etc? Yeah they're big, but not entirely unprecedented. Yes, I know there's only about one or two previous examples. But look at the bloody brilliant minds who drive those pc's, and you'll know exactly why they have such power. They worked the system, and earned the potentials.
Here's the thing though, and maybe its my ever loving internal Fleming perspective, but there is not a single one of you who have just joined the titanic power level, that does not have at least one good exploitable weakness. Even Vladimere Grimme, who showed each and every one of you up quite handily at DEXCON, does indeed have a weakness. Don't worry Gene, nobody's paid Ash enough to spill it, yet.

Second, there will always be someone better, and you are not intended to play this game solo. This game has a definite, and unfortunately overly emphasized at times, PVP aspect to it. Any MMO PVP player wil be more than happy to express to you, that you don't walk in dangerous territory alone, while flagged. At least, not if you expect to maintain a long existence. That PVP aspect, yeah its gonna suck sometimes, and you're very likely to get to points where our resident, and current, "Team Evil" is kicking your solo ass on a regular basis.
Third, there be monsters here, and again you are not intended to play this game solo. For those that haven't quite delved deep enough, Avatar uses strife, and opposition, and power spiraling to create its plot dynamic. Houses set in opposition. Characters set against each other, by the pull of the strings of puppet masters, who stand in opposition of each other. All in all, conflict is an underlying theme, and unspecified game mechanic. We're meant to build the bigger board, with the bigger nail.
So a skill cap. Yeah, just no. It goes against the logic of the mechanics. Every time a "Team Evil", has stuck its neck past the point or irritation, its head gets chopped off. I know this firsthand, as the scars on my neck are still healing.

Quad digits? Yep they're bound to occur. I welcome the challenge and opportunity. I can't wait to devise a plan to take that scrub out, own their soul, or sell some other vengeful nub the tactical knowledge to give them their come-uppence. And I expect to be handed my teeth every so often.
Ok I'm done. Now hand me my hammer. I don't think I need to tell you how to identify it. 8-)