I hope for faster than 1/250 X-sync, since last generation of pro bodies is step back from older models:
1/200 on 5D mark III is slower than 1/250 of 1Ds or Nikon D800
1/250 on 1D X is slower than 1D/1DIII,1DIV
Oh yes! That should be high on the wishlist for a work-ready 7DII. Faster sync speeds are difficult to achieve on FF due to the greater distance the shutter must travel. Dr Neuro has explained this more eloquently.
I loved the 1/500 sync on the original 1D with the CCD sensor, the last in the line before CMOS took over. I did read the reasons why CMOS characteristics did pull the sync speed back from 1/500 to 1/300 on the 1D MkII MkIII & MkIV but can't recall the details. It was a decade ago.
In recent times I have been making a lot more use of high speed sync on the 580ex & 580exII. It really needs a gutsy external battery hooked up to make it truly useful as it sucks power like crazy. I run a twin output Quantum Turbo T3 which is a big help. It's also useful to keep your aperture big and your iso as high as practical for your project, particularly if you need a few frames burst. With HSS there's no problem if you shoot at 8000/sec at f/2.8 or f/4 at 800 or 1600 iso. I'd like to read other people's HSS strategies.
But back to business, yes Canon, stretch the R&D budget, charge a little more for the 7DII if you must but give us 1/500 sync.