I really think being bored at Epcot is a misconception. My daughter is now 8 and Epcot was her favorite park from ages 2-5. In Future World you have The Seas with Nemo & Friends, Turtle Talk with Crush, and the entire The Living Seas pavilion. The Imagination pavilion has Figment and the ImageWorks lab and play area. The Land has Living with the Land, and Innoventions West is home to the Character Spot, Baymax, and Joy and Sadness. There's also Spaceship Earth.
The World Showcase offers KidCot coloring stations, Mexico has The Gran Fiesta Tour and Norway has Frozen Ever After. There are acrobats in China, the Matsuriza Taiko Drummers in Japan, Sergio, the juggler, in Italy, and Serveur Amusant in France. There is also a boatload of character meets, from Snow White and Belle to Mulan and Mary Poppins.