For light loads, one goes to lighter recoil springs. For die-hard competition, one will frequently go to lightened slides.
For POI changes, use lighter bullets to raise and heavier to lower--or use less velocity to raise and more velocity to raise.
I find most recoil is the weight of the slide coming back and I don't really feel much if any significant differences firing 9x19 or 10mm Auto--all I feel is the slide weight recoil and a difference in the boom.
You have nerve damage, so you have a built-in recoil sensor and you may find that you need to go to a lighter, weaker cartridge or even a revolver (to eliminate the irritation from the slide recoil).
If you don't have a lot of experience with different cartridges, you may want to find a range where you can rent a few different guns.
231 is an excellent powder, but for light .40 loads, I prefer AA2 (more accurate) and for mid-range I prefer AA5 (a LOT more accurate).
It is very hard to beat AA5 for any .40 load except full-power loads where Silhouette is best.