A reversing/rear view camera will help - see Bundalenes 130 thread in the projects forum.
You said you are new to 4wdriving, but also you have been around landies for some time so you may already know: Always select centre diff lock when off road. Learn how to drive down steep grades with an auto.
I like traybacks for their practicality and ease when used for offroad touring. I also like the type of top that Xul for same use.
You loose some performance with an auto behind a 300tdi (even manual 300Tdi's are not great performers when loaded and against headwinds at best of times), so if not already done consider fitting an egt gauge, and tweaking the turbo and fuel injection pump.
300Tdi's can end up with expensive damage if the overheat due to cooling water is loss, or blocked radiator. It is a good idea to fit a low water alarm - their water pump is mounted very high and they can't tolerate a relatively small loss of water (and the temp gauge will not help much).
Replace the plastic plugs in the thermostat housing and radiator with brass plugs. Do this at home and don't wait until you have a problem - they usually break when you try to unscrew them and can be difficult to get the broken part out.
Fit a relay for the head lights (I like the kit that traxide on this forum sells).
Edit: I notice you mention spotties and dual batteries - traxide has good products for these and you should be able to fit them youself from the instructions - else yell out on this forum or discuss with traxide.

