Haven't had much time to play it online (so no belts for me) but playing with friends is pretty boss. The hijinks you can do in this game are so entertaining! I mean, c'mon! How can you not enjoy smacking Kratos around with a sturgeon?
I will agree with Cyber6x, however, in regards to the arcade mode being rather crappy but I can forgive SuperBot for it. They were trying to emulate the arcade modes of traditional fighting games which usually only have still image intros and outros with voice acting dubbed over them. I think people were just expecting that this game was going to emulate Smash Bros. to a t but they failed to realize yet again that All-Stars has its roots in traditional fighters more so than it does in Smash-style games.
Also, I'm pretty sure that SuperBot had a much smaller budget when working on this game than HAL Laboratory did with Brawl. I mean, c'mon, think about it. Brawl was the third entry of an already well-established Nintendo franchise that had two other games to learn from and improve upon (debatably, this may not be the case for you). However, this is All-Stars' first game entry, let alone SuperBot's first game as a company. Considering this information, I think we're being too harsh on the dev team for falling short on one aspect of a game when the rest of it is phenomenally handled.
I have to admit, though, that fighting on All-Star mode makes for some pretty intense matches the further you get into the arcade "story", especially those rivalry battles. It makes you feel awesome when you win each one of them that you just want to shout "YEAH!" every time.
Regarding the two Coles, we can't really fault SuperBot for that as it was Sucker Punch's decision to have him as two separate characters, not theirs. However, I will mention that when you consider the ice and fire powers, techniques for playing them are rather different. The ice powers make Good Cole more of a technical player while the fire powers make Evil Cole more of an agressive brawler. Suffice it to say, me being good at one and sucking at the other is enough differentiation for me to say that SuperBot handled the situation sufficiently.
Also, I wouldn't say that Raiden is overpowered. He's pretty good, but I can handle a few characters better than him. Of course, that's all subjective. I think they're all pretty overpowered to be honest and, in a funny way, this sorta balances them all out.
As a final note, I'd also like to mention the accessibility of the game for newer players. When I had two friends over to play the game with me, they were easily able to fight well with whichever characters they've chosen and have even been able to beat me, someone who's been playing the game ever since the beta came out, several times. I find that to be amazing. Many fighting games rarely accomplish this and I applaud SuperBot for doing almost everything right.
Overall, it's a 9/10 for me. I can't wait to see their future entries into the franchise.