Pete, have you considered trying to devise some sort of handle extension for the front handle for transporting the yak to and from the truck? Maybe some type of rigid extension that would allow you to leave the wheels near the middle and keep the yak in a relatively horizontal position while you pull it, without having it bounce around like it probably would do if you tried to use a rope extension. This wouldn't help with loading/unloading but might make those long trips to and from the truck a little easier.
The farther you can cast, the easier it is for a fish to take you into your backing. I seldom see my backing . . .