Caps is a fantastic key to use for things like backspace, but if you want even more functionality, try using it with Colemak as a modifier that puts all the other common keys right on your home row: http://forum.colemak.com/viewtopic.php?id=1467
(I have the older "international" version with a number of blank keys. I remapped the left space bar to command and the lower left dead key to hyper. Tapping either shift of course generates a paren.)