Molatovs: This is just a terrible idea, they need to change the way these do damage to make them more of a cover denail and not as a fight winner – its just a I win button for any inf engagement.
I don't see what your complaint about 'I win fight' molotov's is?
They are cheap and spammed because they are semi-useless against any infantry that can move and most often you will throw molotov 10 times on infantry without killing single model or 1-2 at best. (providing that opponent is semi-decent and moves out of molotov)
You do that to flush them out of cover primarily, and in doing so often lose number of models.
They are not performing very well as area denial either as 90% of time you don't even need to move mg42 from molotov, still only losing 1-2 models.
Sometimes you might have squad wipe, other times it will do absolutely no damage at all.
If you have problem with molotovs killing your infantry, make a medic bunker. The only times they are doing some damage is when units come to fight in pretty bad shape.
Molotov will most often do nothing to healthy squads
Mg42 that is supported is very hard bite for cons, and you have plenty of time to reposition with minimal loss of MP while dealing a lot more.
I agree with rest of your suggestions about crits / RNG / Armor etc