Well....the Americans used lots of Sherman Variants lol. The Pershing would be fine to be added IMO, but shouldn't be in a commander for the same reasons the KT shouldn't. Everyone would just take that commander and nothing else.
The Jumbo could be a interesting late game call in, maybe price it the same as a KV1? They are essentially the same tank.
Yes but you don't see the point.
For example, Calliope or the one with flamethrower. They are Shermans but they are different.
Right now we have only thicker armor or better gun. It's boring like hell.
For example, we have 3 KV tanks but they are all different.
Damage sponge, assault gun and flamethrower. All are different.
Sherman Jumbo would be just Sherman with thicker armor, that's all and we already have many Shermans that are not so different from each other.
And the KV1 sometimes is useful but if you erase B4 from that doctrine, Im telling you that you will never see KV1 again. Same would be for Jumbo.