Unfortunately no that doesn’t work as I’d hoped. It seems to miss two scenarios:
I could potentially work around the second one by using the “(sub)” prefix consistently for sub-tasks - It may just need a second pane. But I don’t know how to work around the first scenario where there may not be tasks (or any items, for that matter).
Oh also, the hashtag in the filter box is being highlighted by the tag coloring - I don’t know if that’s deliberate but it’s not desirable IMO.