Seems to be very complete, only additional feature i can think about would be that a user could change somehow the account type, for the case that he does not longer wants to be a member of facebook.
Then, I am not sure, but when he cancels his permision for accessing his basic data, he somehow needs to be neutralized in the database, may be setting everything to anonymous.
Besides I allow me to recommend the http://thinkdiff.net/facebook/php-sdk-graph-api-base-facebook-connect-tutorial/ and http://thinkdiff.net/facebook/graph-api-javascript-base-facebook-connect-tutorial/ tutorials which seem to be well done.
Especially the discussion around could be of interest.
monk333