Lots of people prefer planar for classical music, but not for me though. I had a planar before and thought it was good for classical until I optimized my power amp and turntable to fit my small dynamic speakers (ProAC and Celestion + REL sub.). Actually, once set up right, my monitors have a soundstage as big as ML, but better focus and image. My room is not big, so not 100% fair to ML. The integration of bass/high is always a problem for planar. And planar tends to have a tuff time with old recordings(lots of good stuff for classical there). So I choose the music first, no way I give up not playing Horowitz or Rubinstein because my speaker don't like the recording engineers. I believe most of classical fan will let their music choose the speakers not the other way. Planar did have the best high to my ears but not overall integration. If you are fortunately to have a properly linked gears, dynamic speakers are 90% as good in high and much better in med/low. Try violin to cello, planar has to pass this ultimate test first. If you like it, then stay with planar.
This in just my ears' experience, no offense to planar speakers and fans.
Did you ever try ProAC, VA speakers, some say good for classical. B&W and Dynaudio can handle pretty loud music, so it would be good for pop and orchestra. 9NT seems more friendly to old recording (compared with its own N-series). Dynaudio needs lots of power, if you have it, should be good. So, I suggest to choose based on your power amp. If you have good clean/high power, 1.8II is good and if you don't, 9NT is a safer bet. Why not try it on your amp.