Thunderbird task management improvements

[Rekursivs]

Task management is an important productivity tool.
In Thunderbird, it is not fully effective, and here are the first few improvements that are quite obvious once I first tried to use Tasks in Thunderbird.

1. Task priorities must be available for setting with a keyboard shortcut. Right-clicking and navigating through cascading popup menus is contrary to fast task-oriented work approach. Therefore single key tagging (just as star marking and numeric keys work on emails) is highly important for tasks!
2. Task categories not available for setting with keyboard shortcut. The same as priorities, but more extended, as there might be many categories. Should be a very fast and effective way for selecting a category. An idea would be:
   1. firstly invoke a dropdown combo menu with a keyboard shortcut
   2. then start typing the category in a dropdown, which automatically filters the necessary one
   3. then press enter, and the category is set. DONE
3. Task categories list not editable. Sorry if I'm wrong, but I could not find a way to delete the whole bunch of default task categories. Adding my own category in such a long list, where the current list is already complex and the selection process is already tedious - that doesn't justify the effort. Therefore the default list may be as an example, but it must be editable and fully customizable by the user.
4. Task priority and category setting with a single mouse click. Clicking in a task list, on the proper cell where the category information is displayed, should invoke a dropdown for fast category selection. Same applies to priority setting, but as the priority column is very narrow, it might take more steps to plan how it will work. Clicking on such a narrow column might be not an easy task.
5. Task ordering. There should be a way to select the order of tasks. Priorities are good, but what about the particular order? If I have multiple tasks, I still want to work on this one first, and the other one later. So if I could move the task to the top of the list, that would be very much appreciated. Should that be conflicting with current priorities paradigm, I would even suggest dropping the 1-2-3 priority approach and move towards arbitrary numbering of priorities. One may choose numbers 1-2-3 for his priorities and use sorting as before. Or one may use numbers -99999..99999 and use advanced sorting, dragging&sorting and other things much easier.
6. Sub-tasking and indentation. This sounds like a bigger improvement that would involve more technical planning. But indentation and subtasking is a very important feature for effective task management. The more limitless the subtasking, the better. Should it be with unlimited number of sublevels, that would be perfect. Otherwise, just a 2 to 3 level indentation would be a huge improvement, anyway.

Thunderbird