I think NKD is pretty okay. I've played decks with it, and against it, and it seems like the soft counter to it is playing lots of champions (More champs = more attacks). The hard counter is AP denial or Precision. The limit on 3 hits does help against turtley strategies, and I could even see it going down to a limit of 2, but in my opinion, it's no worse than command block and dodge. The major problem with it is it's hard to figure out. It's not obvious, especially when they counter-attack to punish you for trying things out, which can be a big problem for new players.
