Your account has been quite long registered since 2012, which is a reason to add to your chances of getting that done, but your rank is something I may not be able to talk about if the requirements needed for that is inclusive by ranks, but things like this are done base on request through PM to Theymos, he's to decide on wether he can grant you or not, so i will encourage you to do same as others do, give your reasons and attach the old and new username you want to bear henceforth, am sure he will reply you.