As far as reasonable preventative maintenance you should consider the following;
Change front and rear differential fluids, replace with royal purple. Take note of the condition of the old fluid. A good indy should be able to do it. Use caution to fill properly, you do not fill these to the hole, you put in a specific amount of fluid.
Change the Transfer case fluids, replace with Royal purple.
Change the transmission pan with a metal one, and new filter (kit). Put in new Land Rover specific OEM fluid ONLY.
Replace the brake light switch and brake light bulbs (OEM only).
Check for proper operation of roof drains, and inspect for water damage from any previous leaks around the A pillar. Additionally, check the plastic cowl, at the base of the windshield for warping. This is a common leak area. Additionally, consider replacing the outer plastic cover and grommet snaps Left and Right on the windshield. Originals are known to begin leaking at some point, and my experience is the original plastic cracks internally with age on the hold downs. The last one I got in, seems to be a bit more rugged than the original, so perhaps they have improved it.
Consider the age of the battery and realize many faults that occur seemingly unrelated are due to battery failure or weakness.
Replace the swing arm bolts with new OEM improved version. See pictures and write up here.
http://forums.landroverworld.org/showthread.php?t=19422&page=2
Plan on replacing all the belts and tension pulleys at about 100k.
A good independent shop can carry out all of these items at a very reasonable price.
You can order the parts online. I suggest
http://www.landrovermerriamparts.com
It would be nice to learn about areas for adventuring in your area.