Hey, I would like to suggest something that may make Polish in game just a bit more unique as a faction. So Polish Army in the East used Polish ranks and insignia and retexturing FH2 models would make them more unique from Soviets without making a new model with wz. 43 uniform. Should you wish to actually consider my suggestion, here are some references and my proposal as to what ranks imo could be used.
Some references of soldiers in gimnastiorka's as this is the most relevant to the models ingame
As for the ranks:
For "re_light_soldier" just a clear shoulder strap, like the guy on the left on 2nd pic
For "re_heavy_soldier" like the guy on the right on the 4th photo
For "re_nco_soldier"