I completly agree. In high ranked setons it is frowned upon to make t3 subs. People will leave the game for that. The only way they are accepted is if enemy makes Atlantis first, because thats how you counter them.
I also don't really think you can balance t3 subs, they will either be too strong or useless. Maybe they need a different mechanic or just have them work differently to be in a good balance situation
L