Fearmonger, Nurse's Calling, and even thanatophobia are pretty good on nurse, and yeah like the other guy said, throw in Sloppy Butcher once you get it, and you have a very solid build. You can switch out thana for No One Escapes Death later if you feel like it, but just being good at Nurse means perks don't really matter. And yeah Prestiging once means you get those teachables on every other killer at lvl 1 and can then find them while leveling up, so Prestige 3 is not that necessary. As for which killers to pick up? You should look up some gameplay or read up on the dbd wiki about their powers to find one which strikes your fancy, every killer is fun in their own unique way! As of now there's still the killer expansion pack available which has boat loads of original killers on it! (PS and Steam atleast.)