That plugin allows you to manage the sort order on the front end, what would be great is more powerful sorting on the back end for the admins.
The basic filters in the edit.php page are a good start, but they are filters not sorts, ie if you click on a category name you will see only posts in that category, but they are still displayed chronologically.
You also can't build up compound rules very easily eg "show all posts in category 'books' with tag 'paperbacks' and written in the last 6 months, sorted by author".
And before anyone else chimes in, yes I realise you can 'AND' together a category and a tag by first filtering the category then clicking the tag name, but the UI is pretty inconsistent here (why are categories in the top boxes but not tags???) and once you have a lot of articles its just not rich enough.
You also can't create any kind of OR filter at all.