Elizabeth!
This is my favorite part of planning: Where to go on what day!
For the dates that you are going, the crowds are likely to be far larger at the start of the trip than the end. I would suggest you tackle the parks, and the pool day, as follows;
April 6:
Disney's Hollywood StudiosApril 7: Pool Day
April 8:
Disney's Animal Kingdom Theme ParkApril 9:
Magic KingdomApril 10:
Epcot or Magic Kingdom
I put your pool day on day 2, because it will be a very crowded day in the parks. This way you can enjoy a swim and some lounge time, saving a day in the parks for when crowds are a bit lighter.
As for your Epcot question, I love the place! The restaurants make for a nice destination for foodies. The rides, while not as numerous as at the Magic Kingdom, are fun, especially
Test Track and
Soarin' Around the World. But if you are traveling with very little kids, you might prefer having a second day at the Magic Kingdom. I will leave it up to you, or if you write me back directly with more details I can offer more suggestions. Especially dining ones, those are the best!
Have a Magical Vacation!Doug