Elvenking would have to be my first choice after a lot of thinking. They'd make a solid #3, even "odd-ball." .. I'm considering putting in a bid for them. If anyone is interested on splitting it, possibly 3 ways, PM me. Regulation: They absolutely MUST play Regality Dance.
Iron Savior is another one I've seen get quite the unnoticed press around here, and think they could be THE Power Metal headliner to blow the roof off the building next year. I would REALLY. REALLY. like to know they're somewhere on the "to do" list. I would also love to put in a bid for them, see above. + Piet is god, so I can't wait to see him this year.
The third one is tough. It comes down to a few... Tuatha De Danann would be a fantastic 2nd of the 2nd night, get the happy feet going and all, and could definitely be more of the "odd-ball" than Elvenking, though I'd have Glenn write it up in the contract that they'd have to do Brazuzan - Taller Than a Hill (if you've heard it, you know why.) Sabaton is a huge sleeper, and could definitely pull off either #3 slot, and I think thier overall reception would be much like Brainstorms was. They'd take people by surprise, I'm sure of it. And I know Curufin is going to say Tarot and Dark Empire, so I'll leave him to make that case
And Finntroll, but not enough to plead my case.