Sometimes I would like to edit the tags on a question, but I don't have the 'reputation' to do so. How about taking into account reputation on sister sites? I have over 100K total between stackoverflow and dba.stackexchange, so I understand tagging and make good use of adding/deleting tags on those sites. But I can't do it here.
And ditto for some other actions. In particular, I would like to push about half the [mysql] questions on ServerFault to the above-mentioned sites, where they are likely to get more attention.