The series one land rover is unlikely to deliver in your search for high adventure. I have found them utterly reliable and capable over many hundreds of thousands of miles of driving. There are far less reliable/capable options if you want a memorable journey full of vehicular hijinx. Maybe a turn of the century french motorcycle with wicker sidecar? You have mentioned many superfluous additions to the car which waste space, make servicing more difficult, or add pointless weight and complexity. Even though with the extra six inches of wheelbase over an 80 inch and the extra power of the 2.0L you should probably be more conservative in your packing.
-alternator - generator is more reliable and easily serviceable with minimal spares.
-electronic ignition - regularly fails and sometimes intermittently - points are easier to troubleshoot and carry spares for
-overdrive - waste of weight and space for extra fluids and spares - if you only plan on going 40 why bother?
-parabolic springs - sag quickly off road, though you won't be getting too far off the main roads and populated areas with only 5 gals fuel
-giant overstuffed seating - huge waste of space and limits access to underseat storage and fuel.
-5 sleeping bags? insane - bring one if you must and split time using it. Those keeping watch should remain alert anyway
Dammit, you're right, I am bringing too many luxuries. I thought by skipping chairs and a table and making everyone sit and cook in the dirt we were going light, but you are completely correct, too many luxuries.
In fact, we could save the weight of fuel, and just rope our children to the front bumper, dog-sled style.
Now you have me thinking about all sorts of ways to make the trip more memorable, and "character building" for my kids...
All kidding aside, I have an alternator, and will want to charge phones and cameras I'm sure, so that will go with us. The generator would cost more to rebuild than a new alternator anyways.
Electronic ignition is mostly because I am lazy. I don't want to screw around with points.
Overdrive was free, makes the truck quieter, saves fuel.
Parabolics - haven't decided if I will bother with them. One more thing to do before I leave, the stock ones are working, etc.
Comfy seating - critical to have happy kids. They put up with a lot, but 10-18 hours on a seat that sucks makes them pretty grumpy. I know from experience.
Sleeping bags - Actually I use the Thermarest down blankets if it's not too cold. They compress to the size of a small melon.
Any pics of your Series 1s on cool trips? I'd love to see! Sounds like you've had some awesome adventures.