Both the 990 and the 1070/970 require you to access something on the rear panel to initiate a firmware update (reset button on the 1070/970 and a SVC/OPR switch on the 990), so you would still have to get back there with your hand. What I've done is leave a cable connected and tucked away alongside my 990 (USB in my case, although an RS-232 could be left in place the same way) so that all I have to do is get to that switch. The RS-232 port on the 990 also offers a control interface and the USB port on it doubles as an audio input, so both are probably best left on the rear panel.

Having said all of that, if a future product were to rely only on USB for the firmware update and the rear panel switch could be eliminated, it's possible that a USB port could be integrated into the front jack pack without making a mess of the front panel. It's not a bad idea. There might be interest in having a second USB on the back if it provides an audio input - probably identified as USB1 and USB2 or with each restricted to a single purpose - which would mean we'd be looking at some additional cost.