I think you bring up some very interesting points!
The trek legends/mods like pattern enhance, rescan, etc. don't appeal to me. More common mods (ctrl, shift, meta, super, hyper, fn, etc) would sell me.
I understand your concern, but the main problem with offering the usual mods would be the non-uniform color scheme and the need for so many extra keys. While it is possible, it would raise overall costs for everyone, which I'm not sure is beneficial to achieving a reasonable MOQ. That said, if this is what people want this is definitely possible.
The other quibble is DSA on the Ergodox isn't my preference. I find I really want some varied shape to help with hard to reach keys and homing.
Is a different profile and/or other mod legends possible? If so count me in for two!
I would be open to trying to try to create a concept for sculpted keys, but just like with the mod keys the diversity of layouts makes this very difficult to do with with normal legends. Ignoring this, I'm not sure how well a DCS set would be received, but a sculpted SA set might be interesting (I haven't seen a PBT SA set so I'm not sure SP can do this)