I've played with a naga for years. I can comfortably hit 48 key binds alone with modifiers shift, ctrl, and alt.

Ctrl and shift are really easy on most keyboards. Alt might be a bit tougher depending on your keyboard and your dexterity. So as others have suggested you can bind things around your movement keys which you can double/triple up on with modifier keys as well. I did this prior to having a naga.