I would buff the penal first. The sov sniper is still an excellent but the overall weakness of the building make it less attractive.
Penals only need a slight buff in the accuracy department, since even Rear Echelons will out DPS them when they reach VET 2 (5men) in the next patch, as for the Soviet sniper, i think its fine since i always hated the M3 + Soviet Sniper META from 2013 and the sniper lost its OP Sprint that was very unrealistic
(The only "buff" for the Sniper i could think of would be a VET 1 ability to increase its fire-rate for a few seconds but make it immobile when it gets activated, and a slight speed de-buff (exhaustion) after it wears off, or the player activates retreat, that way it could act as a "tactical" risk & reward ability)