[Klaus]

Canon always has, and rightfully so, taken the position that lens IS is a better solution, and Canon ALSO has communicated from the start of the EOS R introduction that they are working on also offering in-body IS, which you must be aware of.

Once they have a professional durable 1-series implementation it will appear, to work in conjunction with lens IS.

The NEX-7 has those problematic corners, so replacing it with no matter which model will be a good idea, if you want to test any E mount APS-C lenses that is.

On the grand scheme of Fuji X, I see (on the interweb) many who tried them once or for years change back to for instance Canon or Nikon for many reasons (among them problematic artifacts with RAW conversions due to the chosen CFA, colours, firmware/bugs/performance, UI, desire for FF).

Canon is - undoubtedly - the manufacturer with the best lenses. 
And they are - undoubtedly - the manufacture that never had the best cameras. Nikon DSLRs were pretty much always better (less so Nikkor lenses).

There's the DR issue and, yes, after more than a decade of in-body IS on the market, they still don't have anything in place. Eventually, they will but as of today, we are talking about vapourware.
Even the M6 II doesn't have it - despite the fact that it's easier to implement in-body IS based on a smaller sensor.

Regarding the NEX7 & corners - back in the days I tested it vs the A6000 and the A6000 was not improved. The corner performance suffers in the MTFs because 24mp are just too much for most lenses (just as 50mp are too much for most DSLR lenses). FWIW, I will blow off the dust of the NEX7 for a new test of an exotic next week ;-)

Fuji colours - strangely most reviewers love them. ;-) Performance? Sony is faster, yes, Canon M is not. The UI is clearly a matter of taste. Sony's UI sucks but they are still the mirrorless leader.