My suggestion about the ST:
Move to another doctrine (overwatch?) the unit does not benefit form heat round and commander. The unit competes with KT that does benefit from those abilities.
Redesign the unit:
Allow unit to piece world object and ground so that shot become reliable.
Greatly reduce wipe potential.
Greatly increase durability.
Add lots of utility:
The smoke grenade replaced by explosive mines around vehicles vs infatry
Shell do less damage but completely ignore all cover bonus delivering constant damage maybe cap number of kills.
Shell now bypass some of brace damage reduction units can not be used to take 17p the same way Avre can take out 88.
Shell now deliver long lasting debuff to enemy units like:
vs vehicles injured driver,gunner,commander.
vs infatry "shell shock" reduces DPS
vs support weapon "shell shock" reduce reload/ ROF
vs emplacement "shell shock" reduce reload/ ROF
(as for the commander itself make 221 and 223 separate vehicles or at least move fuel cost to upgrade)
