I had the same line of thinking awhile back, which is why I built my buggy and sold my JKU
I do miss being able to drive a jeep on the road, but if you're keeping the JKU then this shouldn't matter. Having a dedicated trail rig is awesome!
IMO....
that cage is ugly. Looks like a stock roll bar with supports added to it. I'd take that out and start over for both safety and aesthetics. Fitting a kids seat may pose an issue, but hard to tell without more pictures
Propane works good, and is a great system of you can conveniently refill the tanks. The downside is that two tanks take up quite a bit of space, and only carrying 1 isn't the best idea seeing as no one usually has "extra" on the trail if you run out. I run propane since I can refill easily, and the cost of going fuel injected wasn't worth it to me. (I may still do it one day if my 304 craps out on me). Most people sell their propane systems bc they get tired of trying to refill tanks.
For the price, that isn't too bad if you want something you can wheel now and fix as you go. A/C is overrated... //SLAMIN//