Check out my thread… http://www.canonrumors.com/forum/index.php?topic=22621.0
Im traveling for 5 months across south and north america and this is my kit after a huge amount of consideration, very similar to yours. (but i would rather take the 5DMKIII than a 70D and 6D)
Top right 14,000mah rav power battery, 1tb Hyperdrive, iPad Mini 128gb, 70-300mm L, 5DMKIII 24-105mm and 16-35mm.
I was originally going to kick out my Canon gear for the Sony A7 but after handling it and the lack of lenses I decided no. I am also going into the amazon for a wildlife shoot so the 70-300mm was the minimum I wanted to take. So I really wanted to shave some weight somewhere else.
I was going to take my 11" macbook air but with the charger and an external hard drive it weighed 2kg. The iPad mini retina is a 128gb only weights 333g and will edit a full 5DMKIII raw file with photoshop express with really good results. The hyperdrive is also iPad compatible and you can connect it via wifi for media and file sharing.
The whole above kit is 4kg. Weight is a big concern for me as I have to carry everything I need for the whole 5 month trip.
My strategy is to carry 4x32gb CF cards, 1 32gb and 2 16gb SD cards. I will write small raw or large jpeg to the SD and RAW to the CF. I will back up all my CF to the hyperdrive for redundancy and keep them in separate bags, then copy all the contents of the SD to the iPad via Lightning to SD reader, for viewing and a little editing on the go.
I plan on writing a blog and editing the odd image to add to it and put on social media. Also the iPad will be used for image review. I was sceptical that the iPad could do all the above but it works very very well really impressed with it.
Might get the new version of lightroom for the iPad as it now allows you to import your images from the camera role.
I also have my iPhone which I am going to use for GPS tracking with the app Geotagphoto, I also have bought the pro cube recharge dock from Hahnel, It recharges two Canon batteries and has a 2.1A USB charger on the back.http://www.hahnel.ie/index.cfm?page=li-ionchargers&id=145&pId=145
I have lots of other little gadgets check out my thread for more info. Hope this helps.