Are you going to use the truck for anything more than an rv puller? For any distance?
Many long bed rigs have a drop in fuel tank to increase range between fueling. Fill up at the lowest price, go a 1000 mi. to next fueling.
No need for a sliding hitch. The genny, pin mounted bike rack, all your stuff can fit in a long bed. What about resale value? The market here is poor for short tbeds.
The turning radius for short beds is minimal comparative to long. Cost of a sliding hitch and less bed capacity should also figure into your decision.
A short bed is right for many people. Look beyond the aesthetics, to choose what is right for you.
Max