Re #1: If you have a reserved seat, I'd show up after 7:30 (unless you're a big Coheed and Cambria fan) to avoid a long line to get in. With paperless tickets, they scan credit cards (bring the one with which you bought your ticket!!) and check IDs, so the line moves slow. If you are in the pit (like me!! -- Cody Cameron, this applies to you too), get there early so you can get close and away from the mosh pit that typically forms about 10-15 people deep from the rail--and don't drink much so you can avoid bathroom breaks that cause you to lose your spot.
Re #2: Definitely get there by 8:30.
Re #3: Get to know the live version of UFO's "Doctor Doctor" for two reasons. First, it's awesome. Second, and more to the point, when it comes on the PA, that's the traditional signal that the show is about to start. If you're in the beer or t-shirt line and you hear that song come on the PA, head back to your seat ASAP. You'll typically hear a mini-roar from the crowd when it starts, too, because of what it signifies. This has been the "pre-intro intro" to Maiden shows for years. Also, if you're in the pit, wear comfortable shoes.
Maybe see you there!