Maybe some sort of increment gear that can be pushed to increment manually (based on a bit width) the unit and potentially lock it in place or something.
I hear you on no perfect solution- it’s something that is built every single day in the woodworking world. So if there is a way to come up with something that would work I think it would be a pretty big deal.
Still trying to figure out a way to do it too… Not a simple answer.
Realize there is a lot of forgiveness and the unit can be moved back to run again if there is some skew. So perfection isn’t necessarily the goal in this kind of roughing tool.