But the problem with treating the tac rifle as a stepping stone for the m60 is that it's an entirely different skill tree. If that was the case the shouldn't the tac rifle fall under the machine gunner skill?
I get it's not a realistic shooter game, but at the very least we can do some balancing with what's already in game to make other weapons more viable as playstyles. Each weapon skill should have a final tier weapon that makes it viable for late game stages. As it stands there almost no reason to choose the smg or tac rifle over the m60 for late game play. You could even argue that the auto shotty falls short, since the m60 with additional perks staggers so often and has such high ammo capacity that it doesn't make sense not to use it, even in close quarters where the shotty should excel.
And if the sniper skill is only meant for single shot rifles, like the hunting/sniper/lever-action, then how do we make them viable in the majority of poi's?