More sorting options when editing a list

Hi!
I created a new list for a genre research.
I then added movies from other lists I found via the tool Action -> Copy from each list I found.
Back to my list, i see that movies that were mentionned severeal times in the sources lists are now featured several times in my own list, which is a bit strange.
I can sort alphabeticaly the view of my own list to see which movies are there more than one time.
But when editing my list, i now only have two options to sort the list in edit mode : Date Added or List Order.

Please could you add all the regular sorting options in the edit list mode?
Or maybe correct the facts that movies can be more than one time in a list?

Thanks!