Inputs & outputs that are not already "normalized" could use switching jacks hooked to connector in the back of the module for the unpatched mode (possibly 1/8 jacks or connectors like the oberheim SEM) which could then be used to "custom normalize" your unit (actually, even those already normalized could be connected to jacks too). Then you could "custom normalize" your synth both within and between modules so that your most common sounds use zero or few patch cables, and you only have to do fancy patches for the less used sounds. But later you could fairly easily renormalize as your sets change (or your module count increases!)

Ron