These are not game changers like the Completion Grants and Ancestral Seals, but if you are constantly harrassed by someone or would just like to disappear for some other reason... these are awesome if used properly. If used wrong, you will have a new name and the same old problems.
Before you change your name, acquire these items as well:
Dark or Charted City Warp
Enough Outpost Warps for all of your Outposts
Rename Proclamation (Optional)
The reason you need these is that even if you change your name, and I know where your City or Outposts are, someone could figure out what you changed your name to. So right before changing your name, warp all of your City and Outposts. If you change your name 1st and then warp, someone may see your new name before you get completely warped away and ruin the point. Renaming your city is not as important as warping, but it may prove useful if you have one laying around or if your City Name is so unique that is sticks out in a crowd.
Also, if you plan on changing your name, DO NOT message anyone in game if you do not want them to have your new name. If someone has an old message from you in their inbox, as soon as you change your name the name on the message will change as well. So you have effectively wasted your name change.