Leica Snob now issit? When I was a lad we didn't have Leicas. We had a piece of coal and drew our portraits on old fish wrappings. And then we had to eat them if there wasn't any broken glass for dinner that night.
There is a brilliant passage in Mark Twain's "Life on the Mississippi" where he describes a glorious sunset scene on the river so that you really wished you had been there. Then he puts on his River Pilot's Hat and lists all the weather and treacherous currents and navigational hazards data he can pull out of that same scene.
One way of looking at this is that we should be careful what we specialise in: even if we think we love it. After really diving in, it will never be quite the same again. Maybe better, maybe worse. Another example: Before Amazon, they used to say that if you loved books, never even dream of opening a book store.
Also 70s cameras were made with too much precision, you might accidentally get things sharp and in focus which is a total waste of film.
Here is my take on Lomotography - you can always make something that was sharp into something that is out of focused, blurred, light leak, etc. But you cannot do the reverse.
6D is fabulous value with excellent low light performance.
IIRC, you lose auto focus if you use adaptors on the Sony. And yes, the battery performance on the A7 is horrible, you need to carry several batteries.
Agree that buying a 5dMk3 at this point is not advisable as it's well due for an update.
If possible, can I add onto your purchase to get that discount? Wouldn't mind adding another Canon lens.