I didn't play CoH1 online so I have no idea how successful it was on the PE, however my first concern would be that 1 selection essentially becomes meta and the other gets sidelined.
It was REALLY great, you could customize vet of your units depending on weapon upgrade you gave them, so you created specialists on the fly, I liked to spec G43 PGs with offensive vet, STGs and shrecks with defensive, worked same way for vehicles, it really expanded how you could play your units and it was great imo.
Now that things got bit clearer, it might only be for US, but it is a great approach to vet system.
I didn't play CoH1 online so I have no idea how successful it was on the PE, however my first concern would be that 1 selection essentially becomes meta and the other gets sidelined.
That's where balance comes in, both options are situational and situation changes depending on map, enemy and your own skill level. We will see how it plays out, but I'm optimistic.