Everyone in the game will tell you that the team balance system sucks.... Many of us have been on teams where you have 2 high level SS 3 high level BB and a high level CV vs. 1 low level SS, 3 low level BB and a noob CV. Of course the team with the high levels will win.
So instead of making the teams Players vs. Players, why not make it Players vs. NPC.
And here is how you balance: For each ship that the player team has on it, the NPC team has the exact same ship on its team. So if you have 5 BB5 on player team, there will be 5 BB5 on NPC team. The difference is that the NPC team will work together better and will not have to do the manual firing.
Example: Player team: 1 DD1, 1 DD3, 1 CL3, 2 CL4, 1 BB1, 3 BB4, 1 CV1, 1 CV3, 2 SS2
NPC team: 1 DD1, 1 DD3, 1 CL3, 2 CL4, 1 BB1, 3 BB4, 1 CV1, 1 CV3, 2 SS2
Equals - BALANCED