The setup you show at the beginning of the thread looks nice. I never like the full platform look I see in truck beds, too close to the ceiling for me.
I'd add a simple, minimum 16ish inch deep, shelf at the front of the truck bed (by the cab passthrough) for your bins/clothes/quick access gear. You can slide your feet underneath while sleeping and keep more room, side to side, on the floor. I suppose you could also cook/boil water on a shelf like this too. Using the passthrough you could access some of the gear from both cab and sleeping area.
If you need more overall storage for campsite/activity gear a roof rack and roof box would be perfect.
