Still that is power creep, even though you pay for it.
That's a problem of USF initial design. Initial flaw. And this problem can't be resolved.
Imagine if pz4 could pay side armor skirts, tungsten rounds for extra pen and he rounds like Sherman's.
But it technically was that way... Elite Armored. Double vet 1-2 Pz.4J call-in, skirts were 80 muni, if I remember correctly. And the tank was better than T-34.
But true, I don't much like the idea of a T-34/76 upgrading into a KV-1, and this is pretty much the same thing.
I think it should at least cost fuel and be mutually exclusive with the .50 cal.
Ideally, ditch it entirely and add some sort of Sherman Jumbo unit instead.
It is still far from KV-1 in many aspects. The only possible problem is potency against infantry... But Brumbar more potent anyway. And 105-mm arguably too.
I liked your idea about icon, but I don't think right now upgraded Sherman overperforms.
Munitions matter far less the later the game goes, and generally get dumped into 1-2 abilities like CAS.
I am totally disagree. Fuels matters less to the point of float, because you don't have pop for tanks. Or you heavily lack manpower in the worst case.
If the cost of the upgrades matters, T34s should be receiving a nerf to their MGs since their hull MGs deal equal DPS to that of the 3 MGs on the p4s, except P4s are required to pay for it.
If you're compare like this, than don't forget how good T-34's main gun in comparison to OST Pz.4 main gun.