I understand what you’re suggesting but that takes time and also needs a proposal with workflow explanations and UI mockups.
I was suggesting ‘workraound’ possibilities, which were not all that good.
Another possible workaround would be to use splines that have overlaid end points. These have to be made separately and then moved together to overlay the end points. Then you can snap to one end and trace along the combined curve:
Edit:Add: I’d refer you to the comments (and useful links) about feature proposals in this topic: