> What's the procedure for changing your name? A lot of people change their name after marriage or divorce. Those are usually handled by the states, so adding a federal government in there raises the net complexity.

To be clear, the federal government is already involved with name changes-- in fact, though my name change was issued by a state court, I had to get it changed with Social Security before I could get a new driver's license.

Similarly, passports do have a sex listed, so that's already something with federal jurisdiction. The passport system is also handled through post offices, solving the problem of needing more offices.