I agree with those above who find the 7D more useful than the 5DII.
The 7D's only significant shortcoming is its crop sensor with 2009 technology inside.
Not unless you get a 5D3 or 1DX will you find a camera more capable of actually letting you take pictures than the 7D. So you will be very disappointed with anything less.
I have yet to try my 6D for full action sports, for instance basketball with a 70-200 II attached. Theoretically, maybe the middle point on the 6D might be able to do it. A lot of times I use four-point expansion on my 1Dx now, so maybe the extra big, extra sensitive point on the 6D will work "like" that, although I wouldn't say "similarly." I just have to wait until I get to something other than a big game, and I've only had big games in the past two weeks that I've had my 6D.
Back in 2010 I finally just sold my 5DII after using a 7D versus a 5DII for a couple of weddings and a few events, and even in those scenarios, I felt that the 5DII made it so much harder for me to take the photos, compared to the 7D, that it was worthless despite the extra image quality offered. So I would give that as my advice, that of all possible options, not to "upgrade" from the 7D to the 5DII. Camera-wise, the 7D is leagues ahead of the 5DII. I know there's a lot of people loving the 5DII, but if they had the experience with 7Ds that I have had, they would understand what I'm saying.
Maybe the 6D is a viable option, especially if you don't do sports. From my experience so far, the 6D is excellent for everything other than sports, and it's much more professional feeling and acting than the D600. Anything above ISO 1600 is also much better quality than the D600.
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Many things that I get paid for could be done in a pinch with a 5D3 and your existing 70-200 II and the new Sigma 35mm 1.4. Besides sports, the 6D would be very good as well. If you are willing to part with your EF-S lenses, maybe you could get the 6D and the 35mm 1.4. You could be an outstanding professional in many areas with a 6D, 35mm 1.4 Sigma, and 70-200 II Canon combo.
For a cheap assignment today, that was all I used, in fact--my 6D with the 35mm and my 5D3 with the 70-200mm II. There were moments I wished my 70-200mm would have been a 135mm f/2, but I survived and got photos everyone will be happy with. There was never a moment I would have found any use the 10-22 or 15-85, nor is there in almost all situations.