Hello, if you are still working on the second version, I have a few ideas, if you are interested.

1. 37mm autocannon (light) (possible stats: AP 5.5, AT 15, Accuracy 5, Weight 0.5/0.8/1.1), this could represent a 37mm AA gun such as the one mounted on a experimental Soviet T-90 SPAA, or the two on a propsed desing on a Panther chassis (known as Coelian)
2. 122-130mm cannon (super heavy) (possible stats: AP 10, AT 34, Accuaracy 7, Weight 7/9/11), to represent the gun mounteid on the IS-1 and 2 tanks along with the main guns of ISU-122 and 130 and various Soviet projects to mount 122 gun on a medium chassis
3. Maybe increase the AT of the 25-28mm AT Gun as even with the Squeeze-Bore Gun trait AT is still less then the 37mm AT gun, while IRL s.Pz.B. 41 outperformed 3.7cm PAK. This could be balanced by decreasing the AP to 0.5 as these guns had no HE shell and struggled to accurately hit infantry due to to having lower rate of fire then at rifles, which have 0.5 AP.

If you like any of these ideas, feel free to use them.