Jacksons had also more armor, they actually could bounce P4 and again, they had self spotting.
M10 was much cheaper at 400, however neither of the two is a medium tank.
Shermans always had 640hp. It also always had 160 armor, it was very briefly increased to 180 and then reduced back to 160.
Even Scott Howi nowadays has more HP than a few years ago. Now it needs 3 shells to be killed. A few patches ago 2 were needed.
Except Shermans, almost every vehicle in the USF roster has more HP now. More HP means more shells to be killed.
Thats why I insist that, keeping Vehicle Crews repair speed the same as day 1, is a bit strong.