I don't think you can bang out all of FW by afternoon
There is a lot more to FW than just Innoventions, there is The Land, The Living Seas, The Kodak What If Labs, The Universe of Energy, Mission Space (which I don't ride, but the postcards you can send from there are great for Family and friends) Test Track, Journey into the Imagination,Spaceship Earth and shows. The fountain show itself is incredible (especially if you have never been there)
The countries are not just glorified food courts and shops... many of them are highly educational and offer the opportunity to learn about other cultures.
My daughter learned how to Salsa in the Mexico pavillion, and will never forget the CM's there who took the time to teach her.
Each pavillion also has it's own live shows... China has acrobats who are phenomenal, Japan has an incredible story teller, UK has comedians and a band, US has a band, Mexico had a singer (she did Selena when we were there and was quite good)
Morocco had bellydancers.
The gardens of China and Japan are absolutely breathtaking.
Let's not forget that there are now PLENTY of characters in Epcot!
Can you tell I LOVE Epcot?
I have never been bored there, and my daughter has been going every year and still finds plenty to do there.