I think 32 spokes on a well-built 26" wheel is perfectly strong. I'm not the lightest guy and that's what I use on my 26" wheeled touring bike (I run 36 on my 700c bike). I'd stay with the XTR hub and 32 spokes if you already have the setup. Indeed, I have that very setup for my 26" wheeled bike, although I also just picked up a very nice set of White Industries hubs built with 32 spokes onto Bontrager rims and am running those now.

The big advantages, as others have noted about some of the higher-end cartridge-bearing hubs is the ability to easily disassemble the rear hub using nothing but two 5mm Allen wrenches (for the Phil, Hadley, and maybe others). Makes maintenance and spoke repair very easy. The cartridge bearings themselves are also handy.