Actually, I would say that game even starts with solo playing. Blue and green cannot help their teammates from start and during all the game. And same with yellow and red, they aren't really able to help their teammates having only 1 knight and being busy reflecting the attack of each other. So even calling such a game "teams" is bit weird. Сhanging teams to RG vs BY definitely improves the game but doesn't solve problems I noted above. Nice try, cool idea, but it still needs some work.
For now,

In my opinion, green has an actual disadvantage or at least blue has an acceptable chance of winning (i have only played twice) because the dead pawns make it so that annoying thing with blacks rooks cant happen and since greens king is right on the edge of the river red can check him and make him lose a lot of pieces while yellow cant really help green much.