I feel that Martha Jones is a vastly underrated character. Her debut episode, “Smith and Jones,” is one of my favorites, actually. I think that the series at large would have benefitted from a little less swooning on her part, but at the same time, I hardly blame her (let’s be honest: who wouldn’t swoon for David Tennant?) and the episodes in which she appears are some of the best (Blink, anyone?). I like that she is, in fact, a doctor (or becomes one) and I think she has a deceptively powerful exit. Of “NuWho,” she is the only character who choses to leave the Doctor on her own terms and when she does return, she’s an even more established, powerful version of herself and I value that very much.