To further distinguish the function of a sidearm from their more powerful primary counterparts, there should be a node on the left that lets you divide the average damage between two of the same sidearm (dual wielding)in exchange for a higher rate of fire.
To maintain balance, the damage from a single shot wouldn't do much but emptying the mag would do what it does now.
Two different sidearms would not be required for this. The one side arm simply becomes two for the sake of the node option. ADSing would not equate to speedy headshots so much as allowing good damage with high mobility until a more powerful primary is reloaded.