I wasn't sure where to post this as I am unsure where to post suggestions for the game itself (as opposed to suggestions for the official websites relating to the game).

But my suggestion is that the Final Fantasy Developers install a feature that enables players to appear as if they are offline for all intents and purposes, even when they are actually online, in a manner similar to the /invisible feature from Final Fantasy XI. This would enable players to have more control over who is sending them /tell's, and would enable players to negate some of that annoying RMT spam that is so prevalent across all servers.