KV series is much closer to medium tanks then heavies.
KV-8 especially with its low armor for a heavy tank.
But don't worry, Relic already promissed some love for KV tanks so they become proper heavies instead of glorified meds 
So your propaganda worked to make the Kv8 even more OP? WP.
Only the KV-1 needs some sort of love, right now the Kv8 is just insane, rekts every and all infantry + AT on the field in 3 secs.
Oh wait...if we are talking about buffs, lets buff the Flamer HT, WASP, Ostwind, Brummbar (which should be better than the Kv8 if we look at the cost of the unit.....fun fact it's not!).
The only Kv8 armor buff can only work if the damage is reduced.