On Starcraft there was this MODE you can play in.
it was that 4 players played as one base. a lot of us on Bnet thought it was fun spreading was easy!
Unit control of 4 tank squads was fun..
4 Acues for a epic 2v2.. could do 3v3 max I guess. good to help train your clan mates sometimes too..
3 players as 1 A.C.U.!
Have an A.C.U. slot
SO there is a lot of ways you can go with this.. You can make them ON and OFF options OR mods or whatever is EASY and also NICE to the players as Easy..
Like perhaps the ACU can be on MOD to build three things one from each player at a time..
the mex can produce 3 mas and 9 mass and 18 and all three can have separate pools so they all play out something there..
some other IDEAS can be added here
You might like this idea. I hope you WANT to help FAF make it happen.
SIDE suggestion.. should add a toggle option to add nomads in Things like KING OF THE HILL!!