It's too soon for Murphy to die, if she's going to die at all. Won't be until Fight Night at least. It doesn't make much sense to me to have her and Harry get their relationship upgrade only to kill it immediately; we either need to love the two of them together and be therefore more heartbroken when she dies, or hate them together and celebrate when she dies. There's a whole aspect that needs to be explored before it can be ended to maximum effect, if Jim decides to end it at all. Personally, I think she'll kick the bucket in the last Case File book, Harry will recede into hermitude, and be called back in from retirement for the BAT.