As you were mostly brainwashed by the Disney Boards as to IOA being a coaster park it is not. There are more coasters on Dinsney Properity than at Universal.
IOA offers Spiderman one of the Best Rides in the Country if not the planet. You also have Dudley Do Rights Ripsaw Falls, A fun Flume Ride. Popeyes and Bluto's Bilge Rat Barges, the Best Raft Ride around. Jurassic Park River Ride with it's Dinasours is the Best. You Have Storm Force and the Small Coaster is Alright. The Dr Suess area has Cat in the Hat, and two smaller Carosel type rides. I would not avoid IOA beuase there is only three coasters, two of which are a a combined attraction, Duelling Dragon's. My Daughter was seven when she first enjoyed every attraction at IOA, even the coasters. Nine Years old is the perfect age to start wheening one off of the Pixie Dust.