An update to the search:
I have bought two pots in Seattle's Chinatown last month: one a Tiwanese from Lin's Ceramics Studio and one a nicely-scribed Yixing zisha. Both were overpriced but attractive and locally available (i.e.,they could be making tea that evening in my home).
The Tiwanese is fully-glazed and holds about eight ounces. The Lin's ping is too shallow and requires a finger through a fast mid-pour. The pot uses an interior metal screen for the spout which works well but a fingerless pour starts less forcefully because of the ping. Given the glazing, teas (except pu-erh) could be mixed freely between brew outs rather than dedicating a pot to a tea type. (I don't think a quick wash gets rid of a pu-erh's smell/taste.)
The Yixing, obviously unglazed, holds about 14 ounces, and is about everything I expect from a Yixing. The ping is deep and rotates freely. Both inside and outside has the right feel. The pour is fast and smooth.
The disadvantage to this and all of the Yixing I have purchase is that they are good for sharing with U.S. teacups but makes too much for my solitary usual drinking vessel at home (a 12- ounce mug ... I know, heresy) or for tradition couple-ounce tea cups. Given the experience, my next Yixing will be smaller to fit a single coffee cup or a couple tea cups. Comparing the quality of this new pot, the other Yixings I purchased may become decorations on a shelf.
The local experience was exceptionally valuable and has honed the search. I did exchange email with Stephane Erler and will buy one of the pots offered within the next sixty days.
I will also add the store selling the first pot is owned by a Tiwanese national. Through a translator, he spoke of the industrialization of China polluting the zisha clay making the brewed tea less safe while Tiwanese tea pots having a glazed white interior and firing at 1400 (or so) degrees prevents it from polluting the tea. I asked several questions, kept a straight face, and enjoyed multiple brewings of a couple oolongs. Note I still bought the pot and one of the medium oolongs. I considered the story the "entertainment."
The advice has been greatly appreciated. Thanks!
cdv