I wonder if peeps who wish for certain things research the good and the not so good, and the relevance their specific item played in WWII.
At 2000 yards, the US 90mm could defeat roughly 73mm of armor with its AP shot, and 87mm with its APC shot. Nothing to jump up and down about, really. Compare that to the King Tiger, Tiger, Panther, and even the Panzer IV H. Compare that to the Firefly's 17 Pdr gun. See my point? For whatever reason the Pershing and Jackson are thought of as being wonder tanks, and they certainly were not. Patton would have taken 1000's of M18's and M4/76mm long before he would have allowed for the slower firing and slower moving heavies.
I'm not seeing much being added that would be "new", unlike the Su-100, Panzer III (and all the variants that can come with the Panzer III chassis), or even the Cromwell (35mph fast firing 75mm), or Crusader (2 Pdr, 6 Pdr, 75mm, and AA variants available).