I think it's best solution to make "penalty zeal" (just like pios had in coh1) where units gets a little nerf when they are close to each other.
I'd suggest - 3% received accuracy penalty (easier to hit) for each squad (starting with 2 next to each other) and up to 6 stacks (7 squads near with total penalty of 18% for each squad), radius like 5-10 metres
For me (when watching Romeo stream) can say that missions are way too short, some mission objectives are retarded (like capture supplies to beat germans, good job) and AI is god damn terrible
4 cons seems kinda MP draining Barton, does it allow enough room for B4 purchase? Also do you not get T4 at all? I find KV1s suffer some against Tigers.
KV-1's can beat Tigers, like 2 KV's beat 1 Tiger with some help from RNG