I cannot think of any good reason to add any of those additional tanks that you mention. They would do absolutely nothing to improve game playability.
Why because they weren't introduced one day before the wars end and didn't have 3 foot thick armor and a laser beam instead of a gun? You do know that the LW arena aren't the only aspects to the game right?
I bet you would want tanks like the M26 or Is3. Hell while we are at it lets just add the German Maus and be done with it. It didn't see combat and didn't even get past prototype stage but we need all the super uber tanks instead of early to mid war tanks that would fill the gaps. <old rolls eyes>
German MausGun - 128 mm KwK44 L/55
Armor Thickness (mm)
Hull Front, Upper 200@55°
Hull Front, Lower 200@35°
Hull Sides, Upper 180@0°
Hull Sides, Lower 180@0°
Hull Rear 160-165@90°
Hull Top 40-80@90°
Hull Bottom 40-100@90°
Turret Front 240 rounded
Turret Sides 200@30°
Turret Sides 200@30°
Turret Sides 200@30°
Max Speed 12.5mph
Production - 2 prototypes