The biggest problems I’ve seen with her are how devastating she is when flanking and how effective the rockets are in close quarters.
Her flanking ability comes from a lack of warning and the huge gibbing AOE. Less gibbing and some pre-launch noise will help this. I think the artillery warning perk should also light up when she starts warming a rocket pointed in your direction, especially dumb fired. If the laser only works in dumb fire mode nobody will use it for flanking anyway.
I don’t see anything done about her close quarters effectiveness. Reducing the AOE will only make her more effective here. The two ways I see to deal with this are a major slowdown and no jumping while pre-launching or add an activation timer on the rockets where if they hit something too soon they fall and explode a few seconds later. Another thing that would help is if shot while pre-launching it could add a tiny bit more pre-launch time making it way harder to time a jump and rocket.
Her ammo dropping is too easy, but it’s not necessarily too fast. I’m regularly out of ammo drops with her. As soon as one regenerates it goes fast, because it takes 0 effort to drop it. I think the ability would be totally in line with other ammo supply if other both players needed to stand still a little before it started dispensing or if they needed to aim directly at her or press something to get ammo.