In Attack mode, you can win if defenders could not destroy the diffuser in specific time or if all hostile were eliminated.
So what the point to carry the diffuser if you can win the by eliminating all hostiles and win the game?
Why you not just make it as a win it or lose it (attack mode)
Because planting the diffuser make it hard for defenders, you need to destroy the diffuser and eliminate the attackers as well.
Do you still think that the game is balanced?