IS-2 and KT have equal stats of armor. And let's compare who deal with infantry better - is-2 with it RNG cannon or KT with it laser accuracy, don't mention that KT have rare miss shots on vehicle too. When OKW call in KT, it can turn the game, but when soviets call IS-2...nothing special. IS-2 don't have blitz, have poor accuracy and it only have equal armor with KT and MG on top and BFG RNG cannon. I don't want to see IS-2 as IMBA, but i want to see it more consistent than now. Because when you put tons of resources on unit, you want to expect from it very good work. ISU-152, KV-2 and KV-8 do they job pretty well (they have only problem in commanders that in not so common usage), they can turn the game, but not IS-2. As said before, IS-2 need rework, it need new active ability and changes, like were made for brummbar.
You live in 2017, KT got IS-2 treatment. It can no longer even hit buildings 100% accuracy.