If you need great tracking, you are probably better off with an EM-1, or a decent DSLR, but the somewhat conflicting interests/needs you have means there will likey be some compromise somewhere. I'd suggest thinking about the key requirements and where you can give a little up.
I have the A7 and the A7R and think they are absolutely fantastic, but then I have a 5D III for when things move quickly. Their IQ is simply breathtaking IMO, the interface is dead easy to use and the operation fairly intuitive.
If you are prepared to compromise a little on the tracking (I've not really tested that bit yet, but it will be nowhere near the 5D III), I'd recommend the stock A7. Unless you are printing v large prints (I do), then up to around 30" there will be little to nothing in it between the A7 and R version. Its the out and our bargain of the two models, with quieter shutter, better flash sync, electronic first curtain, lower price....
For general walk around work, with an emphasis on 'scenics' rather than 'action', I think the A7/R cameras are on the top of the pile. If you intend to print a more moderate sizes, you'll likely not see much of an IQ improvement over the EM-1, but with large prints and at very high ISO the A7 series sensors are stunning. I'm using mine for travel/walkabout stuff and where I encounter action I will work around it (on those rare occasions) because, to me, being able to produce great prints at 30-50" is much more important.
Then there is the issue of lenses. M43 has many more options, for long and fast lenses with great AF. You wont get that with the Sony right now, but you get the big fat sensro in a smaller and lighter package than the Em-1. Take your pick!
If you are happy to do a little zone focusing and anticipation, rather than tracking using fast long lenses, I am sure the A7 will be fine.
I've not tested the weather sealing out yet and have not heard any comments either way really.