Since this thread started, I've been thinking about this question (under-rated shape) and also looking at a few mentioned shapes. I am surprised that other than Dunhill, not too many pipe makers, artisan or factory, regularly offer pot, and I mean the basic cylindrical pot not the Iverssaon sort of scoop configuration. They certainly are around, but you have to work at finding them, and often they are quite small, or in very low-level lines, or otherwise not typical. When people mentioned the pot shape as being under-appreciated, I thought not, but now I think they're right. Dunhill is still in there with them as a standard classic shape, but not too many others. Shapes come and go in fashion, so maybe the pot is due a revival and everyone will have them in three different finishes. We'll see.
Also, the ball, the spherical shape, is somewhat rare. You find them, but not that often.