I do agree on the seige mode being less practical since you could just get it to Vet 2, the range bonus it gets is good enough to attack ground tragets from a safe distance.
However, I do still think it needs atleast health bonus at vet 1 or 2 is needed, since a single P4 could blitz behind and kill it if microed well.
And yet that single p4 would lose is the kv had literally any support... Like it should... Elefant, Jagdtiger, isu, jp4, su85, su76, firefly, brumbar, sturmtiger, even the king tiger will all lose if you let an enemy circle strafe them to death. The game is about supporting your army. Support your army....