Get an MMO mouse.
The brand doesn't matter (mostly), just as long as it has a shit ton of buttons like above. Use the software for said mouse to make the buttons correspond with keys on the keyboard, and then proceed to map random ass game functions. I have my mouse key mapped to random ass shit like ; / \. You know, the keys your movement keys hand will be nowhere near, and then I adjust the in-game keybindings as needed.
With my hands on WSAD, I find it uncomfortable to stretch down to shift and control all the time, or up to the number row, so those sort of functions, I have on my mouse.
All of those buttons would get annoying with general use PC stuff, so I have a regular mouse for that kind of shit.