I have just bought a second-hand XPro2 and a 35 f2 XF lens, to try out against my Sony A7r (Mark I) with FE 55 lens and my A6500 which I use either with a Loxia 35 or a Sony 35 2.8. A few test shots on the XPro2 look very promising but here are some random comments;
1. Having dithered for a long time between MF, AF and back button AF, my current preference is AF and a shutter button that has a clear half-press position to trigger the AFS without accidentally firing the shutter. The XPro2 meets that requirement.
2. I mainly use aperture priority and like to be able to glance down at the camera and see what aperture is set without having to look at the back screen or bring the EVF up to the eye. On my D810 there is a display window on the top-plate that shows this and other settings but mirrorless cameras are too small to have a top window so I prefer a lens with an aperture ring on a mirrorless camera. Most of the XF lenses have an aperture ring as well as being AF whilst only the MF Sony/Zeiss lenses have them.
3. The A6500 has a fantastically large EVF and its eye point is sufficiently long for me, as a spectacles wearer. It is much better than the small EVF/OVF on the XPro2 for someone like me. I imagined that, having been a film Leica enthusiast, I would like the OVF of the XPro2 but I now prefer a modern EVF for the WYSIWYG aspect including the ability to see over or under exposure before taking the shot.
4. The last comment also means that I appreciate a dedicated exposure compensation dial.
5. I also prefer dual SD card slots, not only for backup purposes but also to split RAW from JPEG so that I can take out the card with the JPEGs and import just them into my iPad Pro for previewing if away from home.
6. Since I am getting older I appreciate a camera that is significantly lighter than my D810.
7. I prefer a less-conspicuous rangefinder-style body.
The XPro2 ticks many but not all of these boxes. The A6500 is lighter, has a larger integral grip, and ticks other (but not all) of these boxes. An XT2 or one of the more recent Sony A full frame cameras might provide more of my desired features but with an SLR style body and with the Sony being at increased cost and weight. Finding a reasonably priced camera and lens combination that meets all my preferences is proving difficult!
Philip