If I could have any band on a huge packaged tour:
Emperor, At the Gates, Old In Flames, Nightrage, Iron Maiden, Persuador, Blind Guardian, Iced Earth, Morbid Angel, Motorhead, Opeth, Old Slayer, Old Dimmu Borgir, Immortal, Borknager, Brainstorm, The Crown and Zyklon...too bad it won't happen.
More realistically I think it would be cool if Nightrage, Dark Tranquillity, Hypocrisy and Opeth did a US tour, mainly to see Nightrage as I've seen the other 3.
Zyklon, Morbid Angel, Arcturus and Borknager for another one.