Re: Switching
It's always been acceptable to switch in MvC2, at any time, even as the winner. It was also allowed for the winner in CvS2.
HOWEVER. In practice, this didn't occur very often.
In MvC2 most teams are strictly good in one order, with a specific "assist only" character, so you're not going to suddenly put Psylocke or Storm first and have Magneto in the back, you're gonna play the team in the same order you just did. In CvS2 occasionally people put a different R1 first, but the R2 rarely moved.
I have no qualms with allowing it at all times, as long as your characters and assist types remain the same.
I look at a tournament as "you're playing in an arcade", so if the game allows you to do it between matches then it's allowed between tournament matches, aside from re-picking your team.
(And if the loser attempts to counterpick I say give the winner as much ability to fsck you on that as possible, you counterpicking bastard. I don't think that's unfair at all. Plus the loser can pick their team in the wrong order, too, to further obfuscate the whole thing, and maybe the winner screws themselves over as a result.)
BUT I'd like to propose a thing, if people do mind that extensively:
You can switch your team via the loading screen as long as you're not the winner of the last game.
So first game, any order -> any order for both players. THIS is the real mixup anyway, and why I would not like to say "no you can never do it".
Second game and on, loser can still do it, which doesn't really afford them anything other than like 2 seconds of the other person mentally preparing for the other character.
(A small bonus of this is not having to go back to character select for the loser, which saves some time if they remember to do it.)
I personally am in favor of just "you can switch order whenever" because I come from MvC2. But I can understand that this community is not MvC2.
So there ya go, wishy-washy as all heck. :^P