Pretty simple. Disable nicknames in PM. When someone PMs me I should't have to use /rn to figure out who it is, and it's even worse when that person is in vanish. I would not know who that person is. That person could be swearing at me in PM and I wouldn't be able to do anything to stop it. This person could be making an agreement with me, and I wouldn't have /rn to see who he is. There are so many problems with nickname+vanish. That's why nicknames should be disabled in PMs.
I never use /r because it's way too easy to accidentally PM someone else. While it's a solution for some people, it's not a solution for everyone.
I know what you're talking about. It shows the username. But that's not something you can do when you get PMed by multiple people. Besides, most people don't know that.
+1 make ingame contrasts vary easy to in force and also as @kukelekuuk00 pointed out /nick + vanish and multiple people pm'ing you it could be vary helpful.
