Why would a Jadgpanther be a super tank? It's a medium leaning on the heavy side like the regular Panther, with even less AI ability. It would fulfill an excellent role that Ostheer sorely need, while not being as boring and OP as the super heavies.
The Jadgpanther wasn't obviously the most prevalent tank, but it makes more sense to have them in the game than fucking Sturmtigers and IR bullshit.
It has the same gun as the elefant, and as stated it would be slightly more mobile but have less armor. Might as well have an su-100 with slightly more pen and armor than the su-85 (in which i find little point for it to exist)
The StuG class of tanks are assault guns, it makes more sense for it to be a non-turret PIV than a pak on wheels.
The Stug was the most effective German tank of WW2, yet in CoH2 its rarely seen (because of its redundancy and crappiness).
It was mainly used as a tank destroyer (statistics greatly support that), but it tries to be good at attacking infantry while marginally threatening medium tanks, but it does not seem to be good at both, and we can easily see how the same route went for the su-76. Ostheer lacks a cheaper stock tank that can actually combat other tanks at range without being blown to bits. Panther is only an endgame solution.