With the release of SoF I think everyone is excited to try 4v4v4. But what about 6v6? What missions do you think would work well for a more expanded game?
Offhand I can't think of anything that's special or unique that a 4v4 couldn't handle. Something interesting might be to have an imbalanced mode where one player uses more characters than the other, and the two have different objectives.
I would just worry about space in the 'Dome. Disengage rolls are necessary to the game, but I can see too many of them being frustrating and dragging the game down. Maybe scale the teams down for more players. E.g. 3 player is 3v3v3 and 4 player is 2v2v2v2...
I might be missing something, but if you want to do 4x4x4 with some house rules, what's stopping you doing it right now?
If you have the limited edition with foils and metal minis or 2 copies of the game, nothing. If you only have the base game with 8 plastic minis and two sets of the 10 cards both players are supposed to have... Though I don't think the expansion comes with the 10 tactics cards either so that could be a problem.
We've designed game for a 4v4. I mean number of Spaces, Blocked Spaces, Movement, etc. But, of course, feel free to try whatever you want. And, please, give us feedback.