Good cantis and good v-brakes both work. I would build it with V's if it were me. Well actually I would build it with BB7s, but that's not an option for the LHT frame.

XT hubs are pretty much the standard in touring, for the reasons you just described. You can buy better ones, but it gets expensive. Phil's for example.

Your bike is going to be great. Better than mine, and I've put 1000's of kms on mine without problems! Have fun on your tour.