On the prefixing (moderation-bullying) there could be a user-bullying so I would say that in some cases there is a need for using the prefix, even if the only 2 right now are Moderator/moderation and user
Edit:
On the bullying thing, I didn't seem to complete my thought. The question was should we use moderation vs moderator. – Andy
My thoughts:
I am thinking that it could mean two totally different things, but I think that Moderators bullying could fall under user-bullying and bullying with moderation tools would fall under moderation-bullying, or maybe there isn't enough difference to separate the two and we should just use a tag of bullying and then a classifier of user or moderator
I think that we should use the term Community instead of site for these synonym tags, leaving the use a little more general and usable.