What should I add to it

I’ve got a bone stock manual 08´b4000 4.0 v6 Very happy with it so far, only needed to weld some parts of the bed and some other minimal repairs.

What should I add or change about it, would like to help it run for a long time and or if anything helps with gas mileage or just cool accessories. So far I’ve repainted the trim and like how that turned out.

It’s currently got 115,000 kilometres.