Actually, the 6D and 7D2 should be a pretty excellent combo!
They are...it is called the 5DIII
For photographers who want a cost effective crop camera there is the 70D. I am wishing for a 'mini 1dx'. Will be perfect second camera along with my 1dx for 'good light' wildlife work. And I hope the 7d2 has better IQ than version I starting from ISO 100 itself to 1600. Hope......Yep, this is the basis for my earlier comment that I am worried that $2k isn't a high enough price to make the 7DII "professional level"....really, I was thinking "mini-1DX."
Considering it would be $900 more than the 70D, there is plenty of room/need for differentiation. But, "mini-1DX" I'd expect to be on par with the 5DIII in price. As the quick example, if the 7DII was given 63 pt AF, 10 fps, improvments in sensor technology gave us ~1-2 stops better high ISO noise performance, AND there was improved low ISO noise performance at $2k price point....who would buy the 6D, 5DIII or 1DX?
Perhaps Canon does go this route, kill the sales of their current FF lineup and release the fabled high MP FF body (3D? 1DXs?) so they'd get sales from the 7DII and 3D/1DXs for 2014 and then refresh the 6D/5D/1D lineup in 2015 with the improved sensor tech.
Maybe....really, that would be great and make everyone very happy....but I am expecting a more modest upgrade to the 7DII at the $2k price point.