casepase8
Typically, I am never one to comment and/or criticize peoples decisions on the internet with camera gear. How ever, since I am in the same boat as you building a new kit I thought I'd put in my two cents!
Like you, I am currently re-configuring my own kit. Primarily my workflow is portrait, weddings and track motor sport. So for me, I have been doing some heavy research on what my best options could be. Sony's A7 body was really attractive! The size, weight, lens opportunity and image quality screamed at me and seemed like it could be something to consider for my price range. How ever, I decided to look things in a different light.
For me, the Sony A7 would have fulfilled every need in my workflow. One thing that really scared me was the battery life. From what I have read on several photographer blogs and review sites is that the battery doesn't even last 300-350 shots. Recording 1k-3k images per event, shooting 8-12 hours in some occasions and relying heavily on a strong battery this pushed me away. The other factor was the full frame NATIVE lens library Sony currently offers. Because the A7 would be my only camera system and I do not own a separate Nikon/Canon kit, it made less sense to have a system that only offered a few Sony/Zeiss branded NATIVE lenses. Metabones does offer a converter that can help counteract that downfall, but you do lose performance in auto focus (only offered with Canon mount lenses) which in return could lose the shot you could have had.
With that said, my post was not designed to bash your decision to move into the fresh and new A7 camera system. It was simply to look at this investment from a realistic point of view. If this is your ONLY system, maybe you should reconsider. The A7 should serve you well, but considering the Zeiss 55 1.8, Zeiss 24-70 f/4 (supposed to be amazing) and the Zeiss 35 1.8…just to name a few… are a few viable lens choices currently for purchase it could be hard to cover all of your bases during shoots.
I decided to go ahead and build up a high end Nikon or Canon kit (still deciding) and later in the future pick up the Sony A7 with a Metabones adaptor and take full advantage having two different systems after I have a reliable and established system for my workflow. This allowed me to focus on what exactly would cover my bases to MAKE MONEY. If you're in photography to make money, then you need to look at it as to what would bring home the cash. Below, are my plans for my kit of which these three pieces will cover all of my needs and later allow me to expand into some high end prime lenses or even the Sony A7 with an adaptor if I chose.
Canon 5DMKIII
Canon 24-70 II
Canon 70-200 I
OR
Nikon D610
Nikon 24-70
Nikon 70-200 VRI
Good luck with your decision, and I cannot wait to hear how the switch goes for you!