Feature Request / Suggestion: It seems that a functionality and UI for the following would be quite useful: allow a user to visually (drag and drop) rearrange task hierarchy (at least, with a single project, but, perhaps, across projects as well).
Use case / Rationale: currently, in order to convert a 1st level subtask to 2nd level subtask (of the current task or another one), a user has to delete the task in question, navigate to desired task (in this case, a subtask) and create a corresponding subtask there. When applying to significantly large task hierarchies, this process becomes very cumbersome and inefficient.