MattW

If Sony stick with their usual (very careful) market segmentation, it'll have just enough limitations and lack just enough must have features such that it doesn't impact on A7 sales.  
When the full reviews come out, I'll bet there are loads of people on here and in other forums saying 'if only it had xx like the A7' or 'why didn't they give it xx, they could have done it easily'.  I'll bet we're all just a bit disappointed...

You didn't talk budget, or I missed it ;-)
The problem with the GH4 (and all the Panasonics) is it only used 70% of the pixels to make 1080p, so you get some moire/aliasing (high contrast edges do not tend to stay where they should, but pop around a bit). You get a much better result shooting 4k and downscaling. It's not awful, the GH3 was much worse, but it can be annoying/distracting.
The A7s or sII will give a cleaner 1080p and the II has a built-in stabiliser (although I think I'd rather have Panasonic's 12-35 stabilised lens on a GH4). Also any low light issues disappear instantly. The GH4 is a better video camera though, just the moire isn't optional in 1080p. (Edit) Oh, forgot to say, the GH4's 4k is cleaner than the A7s', not sure about the mk II.
All IMHO.

I think global shutter is perfect for documentary.

The G7 / G70 also doesn't do HDMI out while recording so you can't use an external monitor, I see that as a major disadvantage compared to the GH4.

The G7 has Zebras and peaking, it just lacks the 10bit hdmi, v-log, weather sealing, headphone and high bitrate Full HD (thats a bit annoying and i dont know why they did it, but downscaled 4k always look good). Its a great performer, specially for the price. But as you said, these things that the G7 lacks are fair enough to someone with the budget to buy the GH4 do it haha In any case both are good performers, they just need good glasses, what i think you already have. For the Canon EF, stick with the metabones, its worth the price, but for the Canon FD, the Roxsen you find at Ebay gets close enough for much less money, just run away from the fotodiox one, it sucks haha

Blackmagic Micro Camera, global shutter

If you are considering the GH4, the GX8 (with a newer, higher-res sensor and 'hybrid' stabilisation capability, but no headphone socket) ought to be on your shortlist as well. Or even the G7, which has nearly all of the GH4 capability (no headphone socket is the main downside) in a smaller package and is so much cheaper that you could buy another secondhand lens or two with the difference...e.g. the 'pancake' 20mm/F1.7 for low-light work and the 45-150mm zoom are both usually around £120-£150 used.

Stills will compare favorably to the RX 10 that is for sure. In Resolve that Macbook will not be enough for 4K. Keep in mind you cannot output anything over 2K in the free version.

I'm confused. The RX10 Mark I ticks every box on your list. Still an excellent camera. What are you looking to gain from this upgrade?