The fundamentals of fighting games are there (spacing, blocking ... other stuff, kinda), but, regardless, with the proper assists and proper options, the fundamentals end up not counting as much as it does in SFIV (not as crazy as Mahvel but can be equally chaotic). Observe. Both Noel and CJ spam Shopping Cart and Disruptor + Teleports respectively until it works. Beyond that, it's predicting the teleports (a lot easier than it looks with no online lag, though YouTube doesn't show it) and punishing the whiffs/dropped combos. Because of the Mahvel system, it literally can turn the match to being won to being lost instantly. This is unlikely to happen in SFIV and I could never see it happening in Super Turbo; the former you can come back because of the Ultra meter and skill, while the latter is (virtually) pure skill. All this considered, I still like playing UMvC3, it's fun, but it's the stupidest kind of fun. Reducing the standard damage from medium to low could possibly solve the problem of spamming or at least hamper it, but, meh, it's Mahvel, so, oh well.snip
Skill is way the hell too multi-layered to be reduced down to an easily definable definition; it can include everything you listed. Like you also said, however, winning is ultimately the goal, no matter the ways to get there. Brainless, like I said, is an exaggeration, but it still has some merit. UMvC3 isn't the kind of game where you learn Wesker's, Dormammu's and C. Viper's BnBs and suddenly you're Umehara, but so long as you're playing characters with the most options and abusing them to the fullest extent, you'll go far (but only so far, of course; skill inserts itself in there eventually).snip
Anyway, I'm both rambling and bad at fighting games, so, take my opinion with a grain of salt.
Changing the topic, is KOFXIII an absolute buy? I know nothing of the game, beyond stuff posted on srk's front page.