That era has passed, thankfully. However, these Bach “B” rims are simply not doing it for my playing anymore. They seem to have a pronounced high point and don’t distribute widely across the face (uncomfortable and squirrelly!). I’ve played a few flatter, wider rims; the Denis Wick is comfortable, and seems to get a clear response on the front of the note (as opposed to the “squirrelly” nature of the 5GB rim). These are just how the mouthpiece responds for me.

The depth of the 5GB is also a great depth for solo/chamber work (with my current playing). I could use something a tad deeper to smooth out the sound in a symphonic/ensemble context, or something with a more open throat. The Bach seems tight in the back.
I have not played through a pile of mouthpieces as many veterans would suggest. This sounds like a wonderful time! Unfortunately I do not have access to a plethora of mouthpieces… it’ll be a few months before I’m at any conferences. There’s no issue in ordering/returning mouthpieces, just trying to get a starting point before making the plunge

What mouthpiece makes would the trombone gurus recommend? I’ve looked into the Greg Black symphony line, the Griego artist series, the Laskey Alessi series. The goal is something that achieves a more stable, rounded sound, with a more comfortable rim (subjective yes, just something without a pronounce high point as the 5GB has) and wider inner diameter. Thinking 4G inner diameter with a cup depth slightly deeper or throat slightly more open at the front, and slightly more weight.
Thanks for reading a long post and all the advice folks