Is the crop 7D going to have more reach? Yes of course. But of course you can just crop the FF image for more reach also.
is the 7D going to yield more pixels vs. the cropped 5D/ yes of Course
Is it going to yield more detail? Depends if the lens is sharp enough. And the 100-400 is not known for sharpness at 400. So maybe not.
On my 400mm f2.8 IS I, my 7D has way more reach and detail than my 5D II (now III)
My 100-400 is excellent at 400, wide open. And coupled with my 5D3, the images are much nicer than what came out of my 50D. I attribute a good part of that to the AF of the 5D3.
So to the OP, you have an excellent lens lineup. I think good AF is a major factor for wildlife. I'd go with either a 7D or 5D3 for the AF... or 1D4, 1DX if you can afford such. If you go full frame, replace the 10-22 with a 17-40 unless you need the extra stop of the 16-35.