This is possibly too narrow a feature request, so I understand if it’s not applicable. I know about the indent and outdent options bound to ⌘[/⌘], and I know that in another thread you mentioned that you don’t like overriding typing-key behaviour.
My proposal is that an exception be made for indenting-outdenting with Tab or Shift-Tab when the cursor is in a bulleted or numbered list. Or even just at the start of a line in a list. The current problem is that, when editing a list, pressing Enter creates a new list item, and places the cursor after the bullet, where pressing Tab to indent the item doesn’t work. Indenting either requires doing ⌘[/⌘], or moving the cursor to before the bullet, adding or deleting tabs, and moving back. The helpful functionality of adding a bullet or number automatically makes changing indentation less usable that it would be without adding a new bullet or number.
Would changing functionality so that, if Tab or Shift-Tab is pressed when the cursor is right after a newly-inserted-bullet, it indents/outdents the item, be possible? I think it’s much more likely that that’s what the user would want to do in that scenario than insert an actual tab character (or 2-4 spaces), and inserting a tab with the tab key would still be available in all other contexts.