Seeing as most people will follow one type of build (WW barb, CM Wiz, 0ZD Witch doc, Face tank Demon hunter etc) I thought that if Blizzard were to add affix's that could alter or change how a certain rune/skill were to work. An example of this would be on a Demon Hunter.
The item affix could allow NT to hit multiple time (as it did on launch) or Increase duration of smoke screen but lose X amount of life per second. This way you would see people building around certain items and creating more fun/diverse builds than we currently have.
Those are two quick examples I thought up. Feel free to come up with some ideas for other skills/runes that could be altered slightly. Dose not have to be Demon Hunter.
And still farming for Leoric's....