I have an XJ (Cherokee); I beg to differ on the ability to wheel on the rocks. Of course it took money, time, and modification to make it so but I have seen almost as much modification on the CJs, TJs and such I wheel with.
As far as fitting 35ö tires on an XJ, I upgraded my axels to a D44 front and Ford 9ö rear, new drag link, new tie rod, cut the front fenders almost off, and put in a 6ö lift. This kind of lift also needs a slip yolk eliminator (SYE, new upper and lower control arms, and another rear drive shaft. No need for a drop pitman arm since the XJs are already factory dropped.
The body/frame does flex. I added an internal roll cage and this helps. A 4ö lift will fit some 32ö tires and not cost a ton of money. The ZJ (Grand Cherokee) lifts are more expensive than the XJ.
Be careful of any Jeep but a Ruby on 35ö tires with stock axels on EBAY. Most had the D35 rear; this is a very weak axel. The XJs with the 4.0 HO had 8.25 (C-clip) rear axels and a few XJs had a D44 rear.
By the way, my XJ cost me $700 but I have spent several grand on mods.