I have a new name.
I tried to trick Google+ into giving me my vanity URL without "a few" extra characters by changing my name to something shorter. I'd tried it before by removing one letter, but I just gave it a second try by removing three.
It turns out Google only lets you change your name three times in two years, making my new surname something I'll need to get familiar with.
It's changed my name on my outgoing email too.
I'm going to have to get in touch with deed poll, or someone at +Google+
I suspect actually changing my legal name will be easier.+Google Support Team
Shaun Chu (formerly Shaun Church).