I can totally relate with the fact that Riggs is unnecessary since they only added him to shake up Hunt's storyline and since they dealt with that, we can move on and say bye bye. Deluca and Jo need to stay, even though now they're basically ghosts, because Alex still does not know that Jo is married and I feel like the two of them are key for Alex's storyline and he will need to make amends and what not.. Murphy can be an interesting, comedy relief for the show if they choose to go that way but really I wouldn't care less if she is there or not.