I find it annoying that issues for which I have created sub-tasks are placed above the regular columns titled 'other issues'.
I've become used to having issues in my 'TO DO' column, and moving them into my 'IN PROGRESS' column, etc and seeing their progress from left to right on my screen as the sprint progresses. If I create a sub-task when I need someone else to do something, then the issue is moved to a row all of its own, and I can't see that same progress with my own issue. It doesn't seem right, but I'm sure I'm simply missing the point, or doing it wrong(ly).