I'll add a little to this. 2 or maybe even 3 mch inputs with independent bass management- my Adcom uses a db-25 port for one of it's two to save space on the back panel. It was a PITA to find a suitable cable for this, but using them to a greater extent would free up a lot of space back there.
Avoid having to cycle through all the dam modes to select a different one. Maybe hit the dolby button and get just the dolbys. Dts button for all those,etc. Logic 7 and some of the other more obscure modes might be nice, but licencing those may be prohibitive.
I'd like to see a small icon on the front panel for each channel- L,R,C,etc and when a channel is live- it lights up. You can tell at a glance what is going on. Maybe one set for the selected input and another for the output.
Perhaps a touchscreen for setup menus- just a thought. The ability to set x-over for each channel independently of course, and how about adjustable slope as well? I like the idea of setting the thing up on a pc and downloading to the unit. My car deck does that- the limitation is you cant hear what your settings sound like till they're downloaded, ability to sync live with a pc sounds expensive. I agree with the optional remote suggestion, they'd have to offer something, but how many would get used if included? Just be sure to supply the codes so the mx-700 posse can go to town.
One last thing- don't be building this thing in china, I wanna see a maple leaf on there someplace.