Well, from someone who bought lots of stuff without really researching ALL the options out there:
I would like to have a stiff spring lift version rather than the air suspension. The D2 drove better when lifted a couple inches and gained the useful tire and ground clearance at the same time.
An after market locking rear diff solution, for front too but likely very problematic.
Exhuast rerouting - as stated previously.
More torque - for the heft of this thing especially with all the heavy stuff added on, and then 4 people and gear, what a slug.
A front bumper that is kind of like the RTE but with upper bars similar to ARB or TJM but not using round tubing because the square edges of the RTE go better with the lines of the LR3 than the ARB does.
Rear bumper, similar in functions to the Kaymar but with quick change mounts to leave the swing arms at home unless you're going to the trail. Also, using locking mechanisms similar to the rear bumper ARB makes for the Land Cruiser 100 series. It's much cleaner and small parts are enclosed inside bumper rather than exposed to damage. Also, tire should be located more center rather than so outboard blocking tail light. It would have been so simple to make this aspect adjustable to user needs.
Yeah, real skids for back half of underside.
camper top roof conversion ....
Japan and Denmark are doing it. It's kind of like a VW camper van deal.
Extended range fuel tank to mount where spare tire went. PLUS skid bridging rear axle to rear bumper.
Better towing receiver - that block thing is annoying. I just want a high located, straight in, 2" like the D1 has.
oh, better throttle response.