If you transferred just to play the game on fight/general content, there's always other servers that are not Balmung that have a decent population. I don't know if Mateus is the "new roleplaying" server for Ex-Balmungers, but if it's not, and roleplay is not your main focus, all you need is some research to know how well populated some other servers are and transfer again. Only Balmung and Gilga are closed anyways on Aether.