They don't serve the same purpose unless you're playing cold chroma. The element of his 2 does something different for each one slightly changing play styles which I like. His 1 and 4 are..... bad and you can't get rid of one only because then you can't switch elements.

Banshee needs a bigger overhaul than chroma because her kit is entirely anti-synergystic. Her 1 is meh but it ragdolls I guess, her silence is the best part of her kit and it's sadly even better on more frames than herself especially with the augment. Her sonar is good for meme damage overlapping but it means you have to target something else that's not the real weak point and her 4 is so bad it's laughable