If core devs trust someone enough to let them act as a PEP sponsor, they probably know at least one core dev well enough to get them to add their name as sponsor on the condition that they are only responsiible for ensuring their "proxy" (?) responds adequately and in a sufficiently timely manner.
I don't have a great deal to add to most conversations here, but I would urge all concerned to consider Brett's point, from my own now distant experience as a PSF chair. If I may paraphrase him, it's easier to change the rules when someone wants or needs to do something outside their current scope than it is to devise bullet-proof rules. It was only after I learned this lesson that much of the constitutional lawyering in the PSF was (gradually) replaced by useful mission-directed volunteer-led activity.
Please don't concern yourselves too much about process, but instead focus on the desired results. If lawyering is needed, delegate it to the PSF! I'd rather have you pushing Python forward ;-).
Finally, thanks again to everyone who contributes, particularly for managing to hide a great deal of Python's modern-day complexity from those who neither want nor need to know about it. Ultimately I think that is perhaps the biggest factor fuelling the language's continued growth.
Kind regards
Steve Holden