Perhaps not the sort of response you seek, but while developing the timbre of the most complex voice, I use it for pitch cv. This frees me up to focus on the timbre without concern for composition while still conveying a sense of how the voice sounds at various pitches.
Once I have that voice squared and the others tuned to it, I tend to switch Marbles to bipolar mode for non-pitch cv. One or two x-outs usually end up in Morphagene while the last is often involved in the more complex voice in some way.
I don’t have a go-to use for the t-outs - still exploring there.