Hi Paull
We have a 2008 Supermatic Regal Off Road that we bought second hand. It had the old leaf springs, a non-galvanised chassis and I had a local canvas guy make the tropical roof. (Do a search on my name and you'll find an item on the tropical roof.) As well as lots of bitumen work, we've taken the camper around the Flinders Ranges, up the Birdsville Track, around Central Australia and recently did the million and one corrugations on the Gibb River Road and the Mitchell Plateau in the Kimberleys, lots of rough roads in the Pilbera, and completed the loop back across the Nullarbor. We tow with a Prado 120 and I've never had any concerns about the suspension. It has worked faultlessly and I'm not sure what extra benefit independent suspension would provide.
So far we haven't taken the Cub on a beach so there are no issues with salt water. Although I've extended the Prado's rear mudflaps and have installed mudflaps at the front of the Cub below its stone guard, the drawbar does get chipped from the odd small stone that gets flicked up. I just repaint it with some silver anti-rust paint when we get back from a big trip and it's fine.
I'm not sure how much Cub charges to install a battery, charger and 12 volt outlets, but if it's in your budget I'd think about getting it done. You can then build your own lighting system after many hours searching through eBay options.
We don't have a driver's side storage hatch. That's the one thing I would really like.
Enjoy your Cub when you get it, and enjoy the adventures you're no doubt planning.
Travelman