Thanks, Dor. Your comments are fair, but after a brief test of Workflowy, I believe I’ve made myself misunderstood. (Maybe I’m wrong. If so, I’m sorry for taking up your time.)
I’ll do what I can to be clearer, at least:
Obsidian already does the first half of what I want in a multilevel list, which is that if I’m typing material at level 2 of a multilevel list, it stays at level 2 until I press Enter twice. However, the current behaviour is to exit the list entirely after the second keypress and place the cursor two lines down.
I’m thinking of the case where I’m typing away on level 2 of a list and I decide I might like to add another item at level 1. I’m trying to say that I’d like for the second keypress to take me back to level 1 – and if in fact I wanted to exit the list, a third keypress would do that.
To me, what I’m proposing goes along with the idea of having custom shortcuts to navigate lists, except that my shortcuts of choice are actually just Tab and Enter.