It seems, currently there are 8 tracks, 8 slots for each track. Will a second instance control another 8 tracks, for example? What about changing the design, allowing more horizontal groups, in steps of 8, let us call those 'horizontal banks', you need another 8 tracks, instead of loading another instance you can swith to next horizontal bank, accessing next 8 groups.
Same in the vertical direction, 'vertical banks' for accessing another 8 slots below it. The user interface needs only 4 more buttons: horizontal-previous-bank := A, horizontal-next-bank := B vertical-previous-bank := C, vertical-next-bank := D
Your QWERTY arrows, up,down,left,right could do those switchings, or other key bindings like j,k,n,p. (j=left, k=right, n=down, p=up)
Back to current situation with multiple instances, are write functions for example automatically synchronized?