I've long been a fan of the Kensington Expert Mouse trackball for drafting. I've used one for many many years with AutoCAD, and now Solidworks.
I've also purchased a 3DConnexion Space Navigator. That combination works really well for me in Solidworks. Moving the model around with the Space Navigator and the cursor with the trackball is very intuitive and fast.
Both have buttons that can be programmed for your most often-used commands. I particularly like the chords on the trackball buttons.
I got a Logitech G13 a few years ago. You can program it with all kinds of commands and shortcuts. It's very versatile. But I never bothered to memorize the layout I'd created, since I already had many of the keyboard shortcuts memorized. So I don't use it very much.