You need to think what kind of role you want to play when driving KV. If you want to hunt, get the small turret 1 with 76mm cannon installed.

If you want to become hidden fixed emplacement, change to turret 2 and install 122mm cannon. This cannon can take out panther in one shot if you hit him but if you miss, you die because the reload time is nearly half minute.

For anybody want to form up with me: IGN ecam

i got my t28 as secondary. got 85mm cannon on it and can take out arty easily so i use it to hunt arty. for heavies i have kv and kv3. german jager for td and su 18 arty for fun. need to xpand the garage soon