Keybinding is highly subjective to be honest, I mainly play with my keyboard using my mouse only for actions like sprint / Limit Break / Shade Shift / Invigorate.
The most important thing is that you must feel comfortable with your setup, there's no "ultimate setup" that will make you win DPS, just a good setup that allows you to use any actions without having to do some finger aerobic.

Same goes for your UI, you must enjoy it but it also needs to be optimized so you don't have to spread your focus in order to get all the informations you need.