Nice thing is, while Trumpeter is trying to get a lot of mileage out of the tooling, they still have altered the relevent components for each subvariant, and I don't just mean the turret shells. As you work through the series, you find that they have anticipated the need for different engine decks, different driver's hatches, different road wheels and rollers. Very cool. Hope they take a break from 1/48th kits long enough to finish up the series with a KV-1S, KV-85 and SU-152. Also like the link and length tracks with premolded droop between the return rollers, and the soft vinyl alternate track is much nicer than the tracks in the Eastern Express or Tamiya kits.
The only real need for photoetch is the engine deck intake grills, and these are available as mini-sets from both Aber and Eduard. Part has a nice comprehensive set that is also good. The larger Eduard set actually has a poorer grill than their small set. The Lion Roar set does not have correct grills, alas, though they do throw in a turned metal barrel.