IMO no point of giving it a main battle tank because they never had one , and they got plenty of AI tanks, so now give to them an AT tank.
Think of it like this, instead of having 1 average pz4. You will have 1 specialized pz2 for infantry and 1 specialized pz 3 for AT.
I know that it might require more fuel and pop , but it's different playing to having 1 average MBT.
what i really like to see for every PE company are ATG/Paks
but its hard to fit AT57mm stats and behavior into a P3 model without looking retarded
so a P3 would be something like a tank unfortunately
and imho the PE has enough specialized units there is no need for an other one....
the bad thing is that everything dies to AT spam but you can't get around of that by giving them an other tank
what they really don't have that all other factions have is something that can support infantry to take out hmgs and vehicles like a mainbattle tank
an other option would be to make the brumbär/sturmpanzer4 useful to be an assault infantry support tank that has bigger stuh shot without being a click ability and almost impenetrateable frontal armor (since it has no turret) like jagdpanther or maybe a hetzer
currently it has shit stug armor no turret and avre shot as click ability