I only changed the Red guys name. Because I got confused when they asked me to name him and blah!
My friend renames them all and it's cute. I have to remember all the names when I talk to her or she gets really lost.
If you change their names it makes it harder to understand what people mean down the line, and when a person refers to "garnet" but you never took the time to learn that your "Ayumi" is really "garnet" you lose in conversation.
But you know who Garnet is, so it's ok.