Not really.
Mediums would become a natural counter to tank destroyers (especially premium meds).
So would LVs be. Two Pumas that can take 4 shots each from a TD would just simply stomp any TD. Even without HEAT shells
And on the other hand heavies would become literally useless. Got a Churchill croc ? 2 Stug IIIs and it is gone ( 2 Shots from each Stug )
The system would just be completely broken.
now you can mindlessly just spam TDs, especially with USF).
Yea ... no. If you only spam TDs , then the enemy will just roam freely with his Infantry
The heavies would be killed as quickly as they are now
No. They would be killed like 3 times as quickly
(maybe 25% is too much, but 20% might be a better idea).
Nice. Now you got a Puma that can take 5 shots from a Firefly.
The lights would be better countered by meds than TDs
Better , but not very well. Ever saw a Sherman / T 34 76 / Cromwell fight a Vet 1+ Puma with Heat shells ?
I hope you realize that this idea is very flawed. No offense, but it would basically screw the whole system.