What functionality is missing? What is unsatisfying with the current situation?

This is but a minor thing but when writing I feel that tags have become really usefull. If I forget the titel of an article I might remember what it was related to and type in that and the "at" system works really well for this (sorry dont know how to do that sign without invoking its power). My only problem is when I want to refrence something directly in the text this instead makes it so that i can't autocomplete by tabbing since the propositions come in Alphabetical order.  

How does this feature request address the current situation?

I propose that the feature still can do it in alphabetical order but order it in articletitels first and then articles that are "at"ed afterwards so that writing can maybe flow a bit faster. The autotagging might make this redundant though.  

What are other uses for this feature request?

No other uses. But all things must not be multifunctional. I like my spoon the way it is thank you!