That's why machineguns have increased auto ranges and high damage ratings, to be more destructive than other weapons when used for support. Tried HMG? Sure the game is a bit biased towards sniper rifles (and bows), but I'm fine with that. Supressive fire doesn't work because AI is too stupid to take heed of flying lead and don't go into obvious killzones.
From gameplay point of view, it's not about making Auto OP (I can easily tweak autoshot ranges and accuracies to achieve that effect). It's about removing the place for Snapshots. Again, you say you don't use Reactions since they're unreliable. Fair enough, I concur that they're unreliable. But I'll say again that I won't tweak the game in a way that suits only a single playstyle. If you want killer reaction shots, it would buff the reaction shots playstyle over any reason.
It is natural for a person who follows a given playstyle that outs and ins of other playstyles appear weak in comparison. If they weren't, the game would converge into a single playstyle, which would be boring.