My old obsolete Pugsley sounds like what you need. I built it originally with the double walled downhill rims(no longer made). After realizing how heavy the are I drilled them. It has a Nuvinci 360 hub, Paul brakes, and I don't rember the cranks. When the first crankset wore out I bought a set out of the take off pile at my LBS. It takes racks front and back, and I don't camp off it, but I have packed out antelope and deer on it. It has been through a few builds over the years, the only parts left from the original build are the complete front wheel and the rim on the back wheel. When the original rear triangle welds broke I was able to get a newer generation fork with the warranty frame replacement that has the mounts for Salsa anything cages.