While I don't know your exact plans, I suggest rethinking your "Bare Bones" approach for these and other reasons:
1. It limits where you can stop at night. In my experience "Most" campgrounds do not have power hook-up for electrical
appliances and, as for cooking outside, it does rain and get cold. There's little as nice as a fresh cup of coffee/mocha in the morning and hot water to wash up with.
savings won't be all that great or all that beneficial.
3. Resale value will suffer substantially as there is a very limited market for that level of RV.
4. It will be much harder to find in the used market, and lead times for new ones are getting very long right now.
5. I'd bet that you spend even more nights in commercial accommodations, wiping out any real or imagined savings.
And, in any event, consider adding an auxiliary transmission cooler to your Lexus, you will need all the protection you can get.
BTW: I drove that same route last May on my way to Chelan, WA from Riverside, CA. Except for the Carson City-Reno section it's a nice drive. LOL