(First time poster, loooong time lurker) I always go for the old saying of "One good zoom and lots of primes". And Im a vintage lens horder so naturally I recommend getting couple of those as well. For the NX I have some Konicas and m42. Here is a quick test I did with a Yashinon 50/1.9, that I payed 10 bucks for, as well as a Yashikor 200/3.5. I think they give a funky look that can be handy for some more artsy stuff.