Sounds like you've got some bad luck with the XK. I can't speak for everyone but rarely do that many problems plague one single XK. The Key battery isn't really the car's fault. The other issues i've not heard anyone complain about really except for the HVAC door which has plagued cherokee's and some commanders. Sorry for the Bad luck. All the problems i've ever had with my XK are things i've caused by offroading it kinda hard. Good luck.
The old ones had some random shut down issues and I believe it was an ignition fault. Haven't heard of the newer than 07's really having the issue.