If you want a Conn Artist 10M I think you should buy one. Great horns, I have owned and played some. But It was not the right right sax for me. The best mouthpiece for me on my 10M's was a Dukoff LD chamber.
There are no balled saxes. There are no ballad mouthpieces. There are no ballad reeds ...... it's the player that is playing a ballad. The sax, mouthpiece and reeds is just helping you to sound as good as possible.
Play and develop your ballad. A ballad from the beginning is a slow dance song with lyrics. Often sad or with a serious touch. I try to play more ballads these days. It just feels better than playing up-tempo rock songs about drugs.
If you like saxophone ballad listen to Sil Austin. A master when it came to "sub tone". Listen to "Danny Boy" with Sil Austin. Sub tones, heavy vibrato, some note bending (I think) .... . According to John Laughters book "Contemporary Saxophone" Sil Austin was playing a Selmer (SBA or Mk VI guess) with a custom made Otto Link #9 mouthpiece.
Good luck with your 10M. Looking forward to hear some ballads or to talk about blues-, rock-, pop-ballad.
View: https://youtu.be/p5C6tQV05YU