The current UX around moving subtasks is insanely convoluted. There is hope though… the main list view offers an expansion to one level of subtask by clicking a little arrow… please allow this to open to any level, just like explorer view in Windows for example.
Additionally, once expanded, it should be possible to drag and drop any subtask to a new location. Just like moving files in Windows for example.
Please please please please please please please please pretty please implement this 
Without this feature I’m kinda lost… tasks keep sprouting but there’s no smooth way to re-organise (menu “Make subtask of” is way too clunky, and drag drop only works under special conditions)
Many thanks!