Why do you people still think the Maxim has "super fast set up time". Last I checked it was 3 seconds, just like the MG-42/MG-34/Vickers. Is that super fast to you?
Do you play anything other than ostheer?
Not only is the set up time the same, the Maxim's suppression per second is statistically the lowest of all machine guns. Talk about observation bias.
Not to mention M3 is in a different tech building than Maxim, but of course he wouldn't know that.
My suggestion for 7-man cons is simply to reduce it back to 6-man, but keep all the other benefits. The 7th model (sergeant) is buggy anyway when recrewing team weapons and doesn't have winter skins either. This would result in a mobilized squad with about 14.2% less both survivability and firepower, which should be more than enough of a nerf.
Even if that doesn't hit the sweet spot, there's ways to fix it. If the nerf is too heavy, remove the weapon slot limitation and make it global. If the nerf is too light, adjust the numbers of the other bonuses. I think the passive bonuses themselves are great for cons, and it would be a shame to get rid of any of them.
My suggestion for IS-2 is to increase it's reload slightly and improve (both) Panthers' penetration. This way Panthers stand more of a chance to trade shots. Maybe even increase JP4 penetration as well.
I don't think nerfing IS-2 armor is a justified decision because of it being one of the few frontline answers to stealthed Raketen walls. I think buffing the intended counters to the IS-2 and nerfing the IS-2's damage output (reload so it's not any less reliable per shot) can go a long way.