If you have problem with countering squishy generalist medium tank that can't bounce anything, its your problem, not balance.
Only really superior tanks require tech.
If you want to bind this one to tech, then so should be done for ost puma, StuG-e and ost command tank together with OKW command panther.
This is correct.
If your enemy gets 5(!) M4C in a 1v1 you did something wrong.
The M4C is by far worse than the E8. It's more a thing between a both T34 types and it sucks agains tanks, especially against the heavy ones.
In addition it's near to impossible to micro 5 tanks at the same time.