I think a lot of the early evening slots (18:00-21:00) are still up for grabs.
I'd add The Offspring, Alestorm, Amorphis, Avantasia, Dropkick Murphys, Accepts, Lamb of God to that list of yours.
Some might also end up in the Marquee of course.
Last year, 2 headliners still had to be...