George, your post title is an interesting conundrum. Since there's no baseline pipe per se, what you like in a briar (or clay pipe, cob, Meerschaum, etc.) is what you like in a pipe made of that material. I certainly like some blends in certain pipes more than others. An Americana blend like Russ O.'s Log Cabin is significantly enhanced in a corncob pipe, a good one like an MM or Old Dominion. A straight burley, for me, likes a deep narrow bowl, room to burn, but slower than in a broad chamber, and a blend with four or more tobaccos often unfolds best in a broad bowl briar. So you draw your own baseline, depending on what pipe and blend or single-leaf you smoke. Which reminds me of the Marx Brothers line -- who do you believe, me or your lying eyes? And someone would contradict each of my preferences for their own purposes, and rightly so.