The
Mage/Guardian frag fest
sounds like fun idea also. I played a lot of Capture the Flag in WOW and it was a lot of fun. I don't think Hero Mages is suited to be done the same way, that is to have to bring the flag back to you team base, but I remember having played another game were you just had to hold the flag for some time on the opposite teams place and that was fun too. That's why I called it Conquer the Flag

but the name is not important.