In my personal opinion, stay away from the diesel, and stay away from the newest variant.
The diesel is costly to have repaired out of warranty, even for just an oil change. The first WK diesels required a wait time of 30min to an hour for the oil to fully reach the oil pan before starting. Granted nobody probably does that, but it is in the service info. We have had one come in under warranty for catalyst and dpf replacement also, and it also got a trans put in it o believe. I know there was a new model V6 that got a transmission, can't quite remember why though. One of the "decked out" models has been in and out several times for a headlight flicker with the HID's. The rear suspension (fully independent) looks like a nightmare to have worked on outside of warranty. Multiple recalls including stupid things like sun visor wiring and the uconnect that could be hacked. I am just not a fan.......
I would buy a WK though, with a hemi. The V6 just seems a little under powered, and at least with the V8 you could pull a trailer if you needed to. Whole working in the junkyard business, we couldn't keep the V6 engines in Stock, but hemi's would last a little while longer. The rear axle is still solid (I know independent is the wave of the future, but I still like my solid axles and full frames confound it). The overall design just seems more jeep than this fiat crap today, and they just seem better built. It seems like more time and money was spent on making a solid SUV of quality, than on making a "pretty" (insert flaming voice) jeep. The only other thing to stay away from on a WK is the air suspension. It is costly to repair and requires a dealer to be repaired, or someone with access to high dollar scan tools and dealer special tools. It has a tank that gets filled with nitrogen. But not just any nitrogen, 0.9999% pure nitrogen. Does anyone here have any idea how hard that shit is to find? Took us two weeks to find a supplier. Bought the tank for a trade in vehicle, and haven't used it since.....and that was 6 or so months ago. Add that to the costly pump, special fill tool needed, and dealer level scan tool needed to perform fill procedure.....and given everyone hates dealerships.....just stay away from the air suspension. It's neat, but not worth the costs.