I think the 2,200-lb Aliner would tow really well behind a GX.
We also looked at off-road campers but stayed away for the same reasons. It's pretty enjoyable for everyone (especially the kids) to stay at a developed campground with electric/water/showers/playground/etc and then take day trips...
For my GX I ordered a hitch for a 2007 V8 4Runner through a local Toyota dealer. The hitch is identical to the Lexus hitch, other than the plastic receiver cap saying Toyota instead of Lexus :). At that time it was cheaper than any Lexus versions I could find. My GX also already had the spacer...
TrailManors pair well with a GX :). I am probably going to keep the 8" as I don't intend to run anything bigger than a 33. With 35s it might be worth it to do the 8.2" upgrade.
I tow our 3,100-lb dry camper with my lifted GX (Ironman FCP and 32" tires) regularly. With gear and water, the camper is probably closer to 4,000-lb, and then we have a family of 4 inside the GX (so total weight above empthy/stock is probably 4,500-5,000 lb considering I have some armor). The...