Power Curve is a bad idea
You say "Power Curve", but all I hear is "dead content".
"P20 and the Mozambique are supposed to be trash, and only slightly better than fists", except they're not slightly better than fists. It is better to play a small hitbox character(Waith, Lifeline, Bangalore) and abuse fists only, then it is to use a P20 or Mozambique.
These guns and other similar guns are just dead content, plain and simple. Pointless and a waste of time and resources to put in the game.
Even the Season Pass is gonna suck, because the only thing in it that isn't complete garbage is the Lvl100 skin for the Havoc. Oh but wait the Havoc is uselss trash. You know what's better than a fully kitted Havoc? A base R301, a base R99, a base Wingman, and a base Peacekeeper. Useless content, dead content, waste of time and money. These guns are straight dead content, no point to have them in the game.
But you won't balance the guns to make them viable or remotely useful, because "muh power curve".