The cannondale T-800 or T-2000 would be the best C'dale on dirt/gravel/paved roads, it's designed for touring, that is long distance and adverse road conditions.
I'd suggest the novara Randanee or the Sahara(26" wheels) but they appear to have vanished in the last month. The novara element seems ok but it would need to have the double crank swapped for a triple.

Oh and cyclocross bikes that have braze ons for racks would be good.