ISU-152 is in team games (3v3/4v4) the unit that gives us the most trouble. Infantry becomes completely pointless while the ISU-152 stays on the battlefield, and if the ISU-152 is supported by Anti-Tank guns or team mate tanks, it is nearly impossible to just go and flank it with tanks (some maps don't even allow proper flanking). Since it also has a lot of health and good armor from the front, you cannot destroy it quickly.
Basically like Jagdtiger and Elefant in that regard, but with the difference that against those you just can send your tanks away and still keep your infantry in the play until you are ready to tackle it, while with the ISU you have to either be able to take it down very quickly or lose map control.
Enemies can also place mines, and since you cannot move your infantry on the battlefield you cannot even use a minesweeper to clear them. If your tanks drive over the mines when attempting an attack on the ISU, you have basically lost the game at that stage, since you are not going to get to that ISU and lose those tanks and are now completely in the disadvantage.
I am not suggesting any balance changes for the units because I don't know what I would change if I were to take a change, but that is how the situation feels to me in those game modes.
This. All this.
Take away its squad-wipe power and then either its anti-inf pwning or its anti-tank penetration/damage. After this reduce the MP cost to reflect its new lower performance. Voila, fun returns to CoH.
Oh and change the maps so flanking is more feasible.
And change soviet mines so they're either more expensive (to reflect the double ability of giving engine damage and high inf damage) or only perform one role (like the whermacht 2 types of mines. 30 munis for a mine that does everything is wrong.