I saw that this project was started and felt it was a great idea, so I've gone around and added almost 30 profiles to get it off the ground.
Most of the profiles already had the display name format of "FirstName LastName, Lord Mayor of London," but for those that didn't, I made the necessary edits. I would suggest using that as the preferred display name to mark all of the profiles.
I did notice that many of the profiles did not having sourcing for the claim of mayorship. I think that should be the next step after gathering profiles marked as Lord Mayors of London -- we'll need to prove that they are indeed Lord Mayors! :)
Again, great idea, and I look forward to seeing how this grows. Let me know if I can be of any assistance.