There are a certain class of system behaviors that apply to new users, not because they don't have sufficient rep within the system, but because they simply are too new to know the culture -- what is expected/acceptable/etc. For example, accepting an answer or creating a good tag. Since these behaviors are intended to help the new user acclimate to the site and/or protect the site from a user with insufficient experience, they really don't apply to people who have been using the software stack on other sites. We should be able to assume that they are sufficiently acquainted with the software to use it correctly without nagging or applying "bumper guards" to protect the system.
This related to a another question I saw this AM about not having reminders to accept answers for users on a new site when that user has sufficient rep not to see those reminders on another site. I posted it as a separate question because I'd like to see these behaviors dropped in toto for users with sufficient experience on another site.
My suggestion (as on the related question) is to use an experienced bit (or bits) instead of rep directly to control these sorts of behaviors. A bit is set on when a user achieves sufficient rep on one of the sites to meet the rep rule for that site. The status of the bit is then propagated to any linked sites, disabling the related behaviors on those sites as well. When signing up for a new site, the state of this bit(s) is copied from your account's previous state. Keeping common information in a single spot would be another (better) way to handle this.