BTER usually doesn't add a coin on launch. Poloniex is the only best option. It has got quite a large number of user base. It has got NXT and NAS already listed. so adding NHZ wouldn't be difficult for him
Polo's NXT volume is laughingly low....I think we should shoot for BTER (and Polo as a second). I've used BTER for my NXT trades without hitch (but their fees are a bit high).