The same way you defend your Arbiter, some one on ANet defends Dragon Hunter. Some guy has an idea and wants it to be ingame, so he is looking for reasons why the name is legit. You do as well.
I see, Arbiter is liked by some people but presuming the community wants this is not really true. Instead of starting a campaign for Arbiter it would have been a lot more democratic to atually ask people what they think a great name would be. Then start a voting with top 20 names and finally have ANet pick one of the top 5 – or something similar.
I don’t think Arbiter is the right choice. It sounds cool, but it sounds really bad in other languages and that is something people don’t consider at all. Other than that I don’t feel this name is that great of an alternative and I won’t support it.
I’d rather stick with the boring Dragon Hunter, that doesn’t make sense at all, instead of just picking a different name because some people like it.
If you want the community back a name change, do it right.