Full boxed frame with adjustable coil buckets and shock towers on all four corners.
Front & rear axle placement extended as far as possible to each end so tires will hit first.
Strong 3 speed T-case with up to 10:1 ratio.
Built in cutting brake option, to add if wanted.
Water tight protected wire harness tube from front to back under body.
Built in wire grommets with water tight plugs in roof front, middle, & rear, for add on's with easy access interior panels on both side A,B,C & D pillars.
Adjustable Cross members for Trans, Doubler T-case, and rear frame for on board air tanks and compressor, with an air hose recoiler all tucked up nicely under body.
Heavy gauge wire ran with universal connectors to interior panel, & to rear for winch, compressor, power inverter or built in inverter with 110 plug outlets front & rear.
Frames with threaded bolt holes for rock sliders like Toyota has on newer rigs.
Hidden DOM Tube roll cage in pillars, and open end connectors (plugged until needed) to add on more tube inside as an option.
Powered connectors in the cowl on both sides for removable manual controlled spotlights.
Seats that will raise higher in the back end for better viewing on angled assents and descents. Compartments in the backs of the seats for storage of valuables, emergency gear items, and locks water tight. Hidden built in DOM tube roll bar protection in seats as well.
Axle tubes with all the tabs for a 3-4 link set up front & rear.
Built it extended brake lines, made were you can adjust the length by removing a small section at a time from frame rail for distance.
Built in locking access doors on the floor for ease of wrenching or replacements of items such as the fuel pump or trans modulator, etc...
Roof rack with strategic mounts for removable doors, coolers, and recovery gear. Throw in a few clasp/eyelets for rope / cable attachment. Have them push into the tube like a pocket knife folds so you can use when needed only.
The normal things already mentioned like lots of skid protection, and HD trailing arms, etc...
OH....Fully water proof submersible LED lighting front & rear, with a optional upper plug in for colored lights, amber, blue, etc... Heck, might as well throw in a switch panel with 12 rocker switches pre wired than. LOL!
I have more ideas, I better stop here though!