i haven't heard of that complaint. question is if it hurts to implement more key strategies which would lead to the allies victory.
at the moment both maps play pretty much the same for the allied team: allied player buys spy, takes the flare and nukes whatever central building suits for cover, usually the refinery.
the nuke either goes off and the allied team has won that match or the nuke gets disarmed and the soviets either win by points in the end or crush the allied team after several attacks.
i have yet to see the allied team winning on zama by base destruction without the use of the flare. i remember that the map got overrun by tanya's and i don't really see such rushes in delta, i'm not sure why.
so your argument that certain strategies would make a map more similar to another also falls on the spy infantry unit. nobody would argu lets remove the spy on missile silo maps to give equal chances on both teams so the map wouldn't play like other missile silo maps, although that sounds interesting.
it's debatable if the gap really makes stuff harder to hit. if tanks reveal themself by shooting i could still snipe away in my v2. i think the support vehicles are good as they are. i only mentioned it in case they would get rebalanced aswell, but it doesn't look like it and it's not necessary imo.