I noticed while playing that mid to late game Soviets are floating a lot of munitions, I mean like 500+ munitions. So I played a game as Soviets and just spammed a ton of mines all over the place, and it is very effective in late game since most axis players have lots of tanks and don't usually get mine sweepers until they notice a lot of mines.
Besides flamethrowers from Urban doctrine and mines, munitions really stack up due to the removal of munition cost on special abilities. And once you get to mid/late game, you pretty much got all the upgrades you need for whatever build you are doing. This allows mines to be placed EVERYWHERE.
I suggest that if the Soviet munition usage remains unchanged, at least make mines take more than 25 munitions.