A system like this could be really good for changing the vibe of a job, without messing with anything gameplay related. I know myself and many others liked it when mch was more gunslinger oriented, or just prefer gunslinger in general, and you could get that vibe out of current mchs kit with just animation changes:

Heated Combo-> unheated animations
Reassemble-> Quick Reload
Hypercharge -> Reload
Air Anchor -> Head Graze (with its impact and screen shake effects back from HW)
Drill-> Rend Mind (honestly the coolest looking mch animation from HW, so confusing why it was used for debuff not an attack)