IIRC, the last I saw of the end-all, be-all of teams ended up being Roberto/Counter-Roberto/Chairperson. Replace Counter-Roberto w/ who you did best against Roberto with. Most tended to just put in Momo or Roy, 'cause they could at least sometimes match the damage he put out, but those who knew about it, Ran, as her keepaway game owned Roberto’s, and she didn’t do half bad at keeping it up when Roberto went on the aggressive.
As for Chairperson, well, any team w/o her is auto-bunk, as she’s there in the same vein as why people keep CapCom, Tron, and Psylocke in their teams in MvC2. Pure assist value. Only less risk here. Team-Up Attacks were a fairly busted concept for the most part, as the only method of stopping it, once active, was greatly in favor for the one who started it all. Jumping away from the one who HAD to land a blow made it rather hard, and generally, the defender of the above team is gonna have no problems avoiding the other for the short amount of time you have to put a stop to it. Your only hope is an air throw, and well, it tends to be easier to run away than it is to run towards someone. At least, for the time you get. It’s possible to stop, but unless the defender is Gan, good luck tryin’ to catch 'em.
Now, Chairperson, by far, has the best TUA. Why? A slight heal and regen all your meter. The meter regen is messed up as it is, 'cause it basically is an attack that gives free meter. Regening wouldn’t be so busted if, ya know, it regened it to 3 or 4. Enough to the point where it would actually cost something to do. Now, tack in a 5% heal for free, and you have the best TUA in the game. Roberto/Momo/Chairperson is fairly busted simply 'cause, on the chance you consider switching from Roberto, you’ve got Lady Deathstrike w/ a racket in Momo’s ability to combo in TUAs. A decent Momo will be able give herself an extra 50% in a losing match (say, against Roberto), and set up for a triple-team at any given time during this time of lolregen. All this, instead of taking a third for another character pick? Pshaw.
I seriously hope there’s another RS game on the horizon. The game is so kooky and fun, and a few tweaks here and there will make it a solid game (fuckin’ Roberto…).