Maybe close off the RFC with a sample /etc/aliases file that has all the suggested names aliased to an account named "admin" including some comments for the ones (USENET) that are likely to be needed on other than a mail server. Remember, this RFC will be read by a lot more newbies than most RFC's.
I appreciate your confidence in this document, but it's not an RFC yet. I am reluctant to do as you suggest since it would require making up addresses to be the targets of the well known addresses, or using real addresses that would ultimately be bombarded by the newbies you keep talking about. (Not to mention that Sendmail is not the only mail transport in town and not all newbies will recognize an aliases file or be able to interpret one.)
You might consider using the domain Example.ORG (sort of the RFC 1918 of domains) if you decide to build some appendixen. You might want to note the prior work done by the NJM working group. --bill