Since the merge, all the progression of each campaign has been joined together. Premium squads from campaigns where those tanks were not common are suddenly grouped with everything else. I think some of this equipment should be placed into the tech tree. There is a precendent for this sort of action, as equipment from the stalingrad campaign was removed, and some premium squads were added to the tech tree during the merge.
Note: Lend-lease weapons and weapons from minor nations (such as hungary) are not included despite any widespread use. Equipment with special properties, such as being amphibious, flamethrower, and having rockets are not included.
Germany
Panzer 3M: 570 Produced
MG 30: >15,000 Produced
Sdkfz 251/1: >15,000 Produced
Stug 3 G: 8,423 Produced
USSR
There are a few mass produced tanks that really should either be added or foldered into the tech tree.
SU-100: 2,335 produced (1945)
SU-76M: 13,732 produced
It is possible that a few weapons, such as the AS-44 Model 5. Could be removed from the tech tree and made premium.
Japan
The Chi-Ha series of tanks were some of Japans most produced tanks. It is a shame that they are locked behind a premium squad and an old event.
Chi-Ha: 1,162 produced.
Chi-Ha Kai: 930 produced.
USA
Most of the widely used US equipment is not restricted to premiums.
(Hopefully the British tanks, Matilda, Churchill, Firefly are included when Britain is added)
I think taking measures to adjust which equipment is premium would help with the “historical accuracy” of matches. Where little used equipment can’t be equipped by every squad and is not seen as often. It also means that iconic and widespread equipment is accessible to everyone.