If you arrive before opening, you can easily ride everything within 5 hours even if the park is slammed, as long as the operations are good and things aren't closed in the morning.
Georgia Scorcher and Georgia Cyclone often open a half hour early so you can possibly ride those before the park officially opens. I would then get in the crowd waiting for the rest of the park to open in the direction of Goliath. When they open, go STRAIGHT TO Dare Devil Dive. That line pushes 2 hours on not-so-busy days so on a Saturday that's the only way you will ride it. After that go to Goliath if the line is just within the station still. If it is longer you can come back to it later. I would then hit Batman followed by Mindbender. After that go to the back of the park which will likely still be pretty dead and ride Superman first, then Great American Scream Machine, then Ninja. Jump on Sky Screamer too if it interests you.
I would also recommend the mine train and even the kiddie coaster if you have time and the lines aren't bad. Other than that Acrophobia and Monster Mansion are the only must rides. Both get a pretty long line.
Thunder River is one of the best looking and most exciting rapids rides are well (I've never seen a more realistic rapids ride. You'd think it's a real river) but you might not have time to even consider that.
I have done all of these within 3-4 hours before on a few Saturdays, so it is much more realistic than it sounds.
Thanks. I found this from July 02. Regarding the Flash Pass, do you have a recommendation?