When doing matching for team, you need to handle the real strength of the team.
This means biasing the value of the highest value tank.
Multiply the value of the highest value tank by two or something.
An S-Vulp @CS 9000 will most likely beat 3 x tier 5 @CS 6000.
It will kill all three once getting lots of points and occasionally be killed for less points than
The tier 5 tanks. No way to win, unless other easy high-value targets become available.