My solution is fairly simple, make a couple level 10+ quests (only on new characters, does not affect existing level 10+ characters) where you have to complete a quest to unlock the /tell, /shout, and /yell, one quest per feature, and a quest to unlock the ability to send friend requests (they can still receive and accept/decline friend requests, but can not send till quest is done). This way it doesn't impact characters that are already level 10+, and makes it a lot harder for the RMT's to conduct their business of spamming tells, shouts, yells, and friend requests to people that do not want to be bothered with them. An average player should be able to make it to level 10 within an hour with very little difficulty, but an RMT will not want to spend hours unlocking those features only to have the character deleted by the GM's for violating the terms of service agreement.