I don't really classify King Diamond as PM. Most PM bands have singers that belt it out, while the King.. Well, he does what he does.
(I like KD, don't get me wrong).
As mentioned, Kamelot kicks fucking ass, Dream Evil, especially the Dragonslayer album is absolutely badass, as is Hammerfall.
Angra and Symphony X are also well worth checking out. Hell, that list ^^ up there is pretty damn solid.
Edit: Firewind totally kills as well.