With regard to the mouthpiece, one idea that I believe could satisfy all vapors is to use a GG style mouthpiece, but put a few threads inside the mouthpiece. Then even with a custom GG adapter (smaller diameter end with threads graduating to a larger diameter to accommodate drip tip), one could use a custom drip tip. This method would reduce the inner diameter of the hole some, but would allow the option. I actually prefer the GG style. But I am one that prefers SS tips anyway. My wife prefers her own tips.
Think a GG mouthpiece with a short adapter like kir fanis made for the iatty. Yes, that adapter works on iatty because it doesn't have GG mouthpiece. But a skinnier threaded end would still work as long as there is enough GG mouthpiece to use that for adjusting flow control.
I have read that there are others that prefer this option and wish the Penelope and ody had it. Penelope would not be as easy since Penelope mouthpiece is smaller already. Odysseus has larger mouthpiece. And threads on the inside would hide the fact that threads exists.
I know there must be a way to satisfy both groups: those who prefer GG mouthpiece and those that want custom drip tips.