The paint is a known issue, there is a US TSB for it - but all they do is buff your paint.
I also have the mineral grey. It does look a little "blotchey" in direct sunlight. I have to say that it gets better as the paint "ages" - after a few months in the sun. My worst spot was in the front of the hood - about 25-30 cm from the front edge. I had 3M clear chip protection film added to the front of my hood and fenders (about 50-60 cm back in the middle) and the problem pretty much disappeared in those areas.
Personnally, I will live with the issue rather than risk a respray on a new vehicle that could end up worst than the original problem.
Some US owners have success with using a clay bar on both the paint and windows for the issues you describe.
If you are interested in US TSB's, here are a few links. Best luck.
Everything about your GC: http://wk2jeeps.com/wk2menu.htm
All TSB's and Recalls: http://wk2jeeps.com/wk2_tsb.htm
Paint TSB: http://wk2jeeps.com/tsb/tsb_wk2_2300312.pdf