if we started with the most used tanks (and usable) still missing I would recommend the StugIII in its different reincarnations, and 50mm and 75mm
Sdkfz251's.
Pershing saw some action, ,and could be the ticket for western allied tank, IS2 is well armoured, but slow, and slow reloading, KV1 is worse than the T34/76 in almost all aspects, SU85/100 would be a real good contender though.
Personally I would like to see the Puma variants also.