...they can bring out (good) aspects of your horn you're not used to hearing.
I totally agree. They are limiting as a full time mouthpiece, but they're a great thing to have around for that reason. There is a fundamental
character to a Buescher sax, not just in tone but tuning and response. Pieces like Buescher, Martin, Rascher or Caravan help you find it. That knowledge can help you evaluate other setups.
A period sound is a neat thing to explore too, if you've ever heard 20s and 30s jazz/pop. However, the pure classical sound - which was just starting to be explored back then - really is best developed by
not doubling on other mouthpieces,
or other genres. Plus, of course, doing religious overtone work. The payoff is a sound that is almost
non-saxophonic...woody and somber...an esthetic really all its own.
As for Meyers, I always got better results with Morgans. I found Meyers hard to voice up top - they could be piercing. But Meyer seems to be the go-to for Buescher and for alto, much as Link is for Conn and for tenor.