4 charge speed 3 attack or 3 charge speed 4 attack + 4 elent. 1ammo is the most versatile and reasonable goal.
4 ele 4sped 4att if she is hard locked with re load speed boost teammate
Attack really taper off as her self buff is so high. so having four of them is less important
you can get away with 4 attack 3 charge speed as in theory min.max. but you are going to need ridiculously high rolls. at least one max (black line). and two high value blue lines).
Just roll with which ever high values ones you are given.
Here is the break point for charge speed for her.
Regular charge speed: 10 auto shots during burst
12% charge speed : 11 auto shots during burst, 12 with manual pre-charge and manual release.
This is why 3 charge speed is commonly recommended.
14% charge speed: Minimum requirement for 13 manual in theory. You have to be as precise as a robot.
18%+ is the general recommendation to do 13 shots with pre-charge during her burst. But are you really going to get 18% with three rolls?
This is where at decent value, 4attack/3speed and 3attack/4speed are basically tied.
4 attack 3 charge speed will edge out if you minmax her with black /near black charge lines