Minor comment on the desired firmware changes is that, with four separate level control knobs on the front panel, to me it would be more logical (and more desirable) to have ganged level as the option, not the default. On the DR680, there's only one level knob so it makes more sense to me that on that machine, ganged mode would be the default.
I would recommend that in ganged 1 x 2 or 2 x 2 mode, either level control 1 or 2 would adjust both channels 1 and 2 simultaneously and either level controls 3 or 4 would adjust channels 3 and 4 simultaneously. Similarly, in ganged 1 x 4 mode, any of the level knobs would adjust all of the channels simultaneously. Alternatively, since level control is all digital, there could be a second menu option to have certain gain knobs disabled in gang mode to prevent accidental movement...say in 1 x 2 or 2 x 2 only knobs 1 and 3 are active and in 1 x 4 only knob 1 is active.
