I have a suggestion. For me alot of the time when i go to a thread then close it and try and find it again, I have no idea what category it was in. So my suggestion is, under where it says "show new replies to your posts" there should be a link that says "Show all threads that you've posted" That way every single thread you've posted in, you can have easy access to it. That would be very helpful
there is already such a link on your profile page (Click your name, then at the bottom is 'show all threads this user has posted in')