Driving time, get on a raptor run, learn to drive the truck. This is the number one thing. Get out and run it as hard as you possibly can, figure out what modifications will actually benefit you. Learn how the truck drives at high speed in the dirt, you will be able to predict it so much better, it will increase your skill in every type of driving condition including snow and ice. Any modifications you make without doing this are just blind.
Maintenance!!!! Fix any problems the truck has, especially in the steering and suspension department. If you've got worn ball joints, shocks, TRE's or the truck is out of aligment no modification is going to be better than making the truck right. This would include fuse 27 and the door seal tubing.
Gen 1: Corsa extreme, very pleasant driving experience, makes the truck feel much more alive, gives a lot of character. Best mod to the truck. Don't put exhaust on an ecoboost, they sound like shit period, the best noise that engine can make is none.
Rigid DSS in the fog light position, one spot one flood. Makes remote roads a whole lot nicer without having to put too much on the truck.
VHF/UHF radio
Rear amber dust light
Drive it some more
Tune it, skip the pedal commander
Spare set of 6 wheels, beadlocked, tire carrier to carry the two spares, good jack, good air.