It needs damage increase, it doesn't do anything well. It kinda can scratch up light vehicles, slightly suppresses infantry. Much too unreliable. I think both both abilities should be buffed.
When you upgrade to Tier 4, Conscripts should be able to upgrade to a DP-28. Not sure whether it would be good for the upgrade to consist of 1 or 2 DP-28s.
Because they have the best MG, best sniper, best mortar, best AT gun (except maybe 6-pdr). And those OP rifle nades, and their core infantry can upgrade to the best LMG in the game. They can make MG bunkers and reinforcement bunkers. Is that not enough.