I just took 10 American friends on a northern liveaboard safari from Hurghada and they all loved it, particularly the Thistlegorm, the Abu Nuhas wrecks, the Rosalie Moller and the wall at Ras Mohammed. Got a hammerhead cruise by on a couple of dives, and even a large manta on the bow of the Moller.
A liveaboard is definitely the way to go to see the best the Red Sea has to offer, especially if you are travelling all the way from the States.
If you want a good introduction to the Red Sea, a northern route gives you world-class wrecks, some nice reefs and a great wall at Ras Mo.
If you want pumping currents, awesome walls, a better chance of pelagics and a couple of excellent wrecks, then a Simply the Best itinerary to the Brothers, Daedalous and Elphinstone is the way to go.
I'm out again in October and November, trips number 35 and 36! I love it!
Mark