Bolt shot could increase vulnerability to wind (making aero dots better and making them more viable for end-game).

Wind shot, however, could have increased potency over the others because; my idea is that it could place a temporaty debuff that instead of messing with resistances "Surrounds target with air (oxygen)" so when hit with a fire shot they would catch on fire for some damage over time. More potency would balance it out.

I was thinking 150 potency for Fire and Ice, 160 for bolt and170-180 for wind because you would get them later. Whatever isn't way too strong. that would add variety to the numbers.

Another DoT could be "Aim-Jugular" or "Aim-Heart." Gotta have Dots

Traits could add the ammount of stacks you can get for Deadeye or increase the ammount of crit chance you get off each stack. They could also increase the strength of the debuffs the ENG causes.