Dear Kevin,
just two very short side-notes on the weight concerns you have mentioned in the article.
The 200-400 is a f/4 lens, even at the tele end. The Sony is not, so in my opinion a proper lens to compare it with would be the 100-400 mark II, which is f/4-5.6 the same way as the Sony is.
The same way, maybe it would make more sense to compare an APS-C camera to an APS-C camera. For example a 7D mark II would be a good candidate.
So if I do the math, this combo would weight 32.1 oz (camera) + 55.4 oz (lens) + 5.8 oz (RRS L plate) = 93.3 oz, which is not that dramatically heavier than the Sony setup. If you add the extra batteries needed for the Sony in a day then probably the total weight would equal the canon setup.
Other than that it looks an interesting setup, worth to try. My biggest concern is the EVF though. I tried an X-Pro2 the other day, and it is just a bit marginally slow for fast paced subjects (fx birds) which requires fast reaction from the photographer. I cannot wait the moment when EVF will close this gap, because it has so many possibilities compared to an optical viewfinder (focus peaking, etc).
Thank you for the great review!
Best regards,
Tamas