If smoke laiunchers would make the difference between your kt surviving or not you're probably doing something wrong anyway. As with every single other vehicle in the game, the kt needs combined arms support if you don't want to lose it to its counters that are supposed to counter it.
Yes, heavy tanks do need support but it's completely unrealistic to state that good play would somehow never put your vehicles in a dangerous situation. As if good players wouldn't ever lose vehicles. Even with a solid combined arms approach and careful play it still happens all the time that your forces run into engagements they can't win, or that you make a mistake or misjudge a situation. Retreating is a core feature of the game and most tanks have a good chance to run away. The KT however, due to its horrendously slow speed and acceleration can not. TDs can just chase it to death with ease. Smoke launchers could significantly help it in disengaging because it breaks LOS.
The game is about risk versus reward, but the risks are too great and the reward is too small when it comes to the general performance of the KT. Smoke launchers or any of the other decent proposals would help put the KT's risk versus reward more in balance.
Not to mention getting a solid combined arms composition is pretty hard when the KT alone takes up over a quarter of the popcap and the only support to hold off Allied TDs the OKW can field are other expensive tanks or Rakettens that are pretty useless late game. The little room left for infantry is usually not enough to kill Rifles or Cons blobs before they can get a snare off.