All to what Grapefruit said and to further it, Although I am very comfortable with my name and player number, I would probably be forced to change it to protect myself from sneak attacks by my opponents under the guise of friendship.
It could ruin a lot of trust that ha been built up with some and allow others to easier steal an identity. I change my name and then somebody changes their name to Stan rogers and creates a reign of havoc.
I think I am against the change as it would impact just about everything I've built over the last 2+ years of gameplay as well as destroy any trusting relationship that have been built. Prevent any recruiting except for new players into the guild. There is enough confusion currently in the game with guild/nation loyalties without tossing in another wild card.
Perhaps I shall see other arguments for this but it has some fairly tall obstacles to get over to convince me to throw away my reputation and try to build a new one. This change means I would be forced to in order to remain competitive.