I like it. I know what's coming next though. Canon is not going to re-badge a 1D4 as a 7D2 and sell it for $2-2500. We could see the same or similar specs, just not in a 1D fully sealed body. Your idea seems reasonable though.
Nah, I wouldn't expect Canon to build such a body in a 1-series chassis. That would be crazy, although I certainly wouldn't complain if it happened If the 7D2 has the same gripless form factor and similar weather sealing and build quality as the 7D and 5D3, that would be fine by me. Considering that many sports shooters already supplement their 1D4s with 7Ds, I can see a camera like this being wildly popular with both pros and enthusiasts. I know you can get stunningly good results with an APS-C sensor, but fitting an APS-H sensor into the 7D2 would allow Canon to easily address people's noise and IQ complaints of the 7D.