Thanks @farkas!
Yes Makrow is worth a serious look for this application! Doing more internet search on this topic, Addac306 looks very similar to FSS Makrow. Tiptop Z8000 might be a fit from a sequencing perspective. Are there other good candidates / techniques to consider here?
Of course the span between sweet spots is sometimes nice sounding, sometimes terrible, depending on the patch. So sometimes I want to sweep the control value, whereas other times I would need to step it.... All this also makes me wonder if there are quantizers that can be set to arbitrary (non scalar) values without a tuning input file; basically a quantizer with knobs that lets you set any step values? With one of those, I could feed any CV input (say a lfo) and custom tune the output to 2 or more "sweet spot" values (which would then feed DPO FM timbre controls).
I do own attenuverters with offset (SISM etc.), so I do have existing options for timbre control with standard CV and/or sequencing. Just trying to go further and have a good scheme for controlling / switching / sequencing a patch's timbre sweet spots, including FM patching.