As long as the name makes some amount of sense to your RP character in their backstory, I think those sorts of names are acceptable. There's a warlock on Moon Guard named Angry, but if you read the backstory post for her on the forums, it fits relatively well.

One of the things to keep in mind is that your justification isn't always enough to keep a name. I've known quite a few extremely heavy roleplayers who have had their names reported and been forced to rename their toons because they were considered non-roleplaying names. They each had wonderful backstories that justified the reasoning for the name (some had it as a nickname, others had it as their name, whatever!), but most were forced to rename their characters (I think perhaps one that I know of appealed and got to keep the name - until it was reported again. Then he gave up).

As both Daniel and Belfaire noted, it's the community that decides what is acceptable and if the GM on the other side of the screen agrees with the person lodging the complaint, there isn't much you can do about it. While I might not advocate this sort of ad hoc reasoning for why things are done the way that they are and would advocate for much more clearly defined rules so these kinds of things don't happen, that's sadly the way that things are.

I don't know, the whole RP Naming thing is a bunch of crap. On one server, my toon named "Harmony" was forced to change her name because it somehow violated the naming policy (even after weeks of badgering GMs with e-mails), while toons named "Punchbowl" and "Healadin" run around despite being reported repeatedly for naming violations.

@Jack Spicer
Keep reporting them. I send a report a day for such names, until they get changed (I add them to my friend's list with a note on what name they had when reported and can see the name change there). Sooner or later the report will end up in the lap of a GM that actually care. Maybe.

One can always hope. It took a while, but finally "Happymeal" on my main server got the banhammer. Now I'm working to get "Crazyfrog" offline as well.