Tbh the whole commander is lackluster besides the repair station and the KV2.
Fuel drop is okay however, what I dont think is needed is the vehicle repair ability and the KV8.
1st
I reckon instead have the scavange upgrade for engineers same as the one in the tank hunter commander.
2nd
A new passive ability that every allie resource cashe built grants the player something like 3% discount on vehicles (excluding the KVs of course). When a cashe is destroyed, the bonus from that single cashe is canceled.
Just a thought.
First idea is good, certainly better than supply drop.
Second idea I can't agree, for one it relies on a peculiar requisite (building any cache, anywhere, and getting pissed when your ally builds all of them), two 3% discount isn't very big difference so it ends up being ignored, three the idea of cost reductions as part of commander unlock don't sit well with me, it kind of competes against (or stacks with) the bulletin system.
I think replacing KV8 with KV1 might be a better option; the latter is far more useful than a heavy flame tank, and acts as a sort of alter ego for T-34/85, where instead of better gun it's better armour.
My own first thoughts, of course.