[code][/code]~ 2 secs reloads are absurd on any tank. Even the StuG doesn't get such with veterancy, and that's an AT only gun, not a dual purpose one as on the LL/E8 Sherman.
Having it for roughly the same fuel price as the Pz IV is what makes it even more absurd, but hey, I guess its only Axis tanks that could over perform for their cost.
Turbo firing tank guns are just bad for gameplay in general since its a massive incentive to just hoard some tanks and roam the map with them Starcraft style with next to nade tactical play involved.
And the Ost P4 gets 30% additional armor at Vet 2 which the Sherman doesnt, you should see how much the new M4A3 76 bounces even on a vet 0 P4.
Sherman gets just more ROF, P4 gets more ROF and Armor judging only by combat relevant parameters.
Still dont see your problems.
Dont agree that fast firing guns are bad for gameplay if the gun in question is higly medicore by itself.
If it would tear through armor like a Panther it would be a problem, but it doesnt.
If it would tear through infantry like a T-34 85 or a tiger it would be a problem, but it doesnt.
If its meh at everything (which it is), i dont see it as a problem.