There is not 1 single gun in bo2 that has zero recoil.
True. Relatively speaking, a few mine as well have none but I think the ones that don't are balanced pretty well. It comes down to personal preference to some degree as well. I like the way some guns kick compared to others, not necessarily because they kick more or less, but the way they kick and re center.
Yeah, but LMGS have low mobility, are slower to draw and take ages to reload that can you get killed. If you're getting killed by one hiding then you have to check your corners. If they're camping behind a shield, leave them and give them a boring game.