We already know what the function of the KH of people's hearts was, it was flat out stated in KH3D. It was basically just a giant Xehanort-converter...
They're not trying to cater to any one fanbase. E3 is the biggest gaming expo so it provides the most exposure. That's about the extent of it.
And I...
Top Worlds for any Future Kingdom Hearts Game 1. Treasure Planet
2. Atlantis: The Lost Empire
3. The Black Cauldron
4. The Sword in the Stone
5. Fantasia
6. The Emporor's New Groove
7. Pocahontas
8. The Rescuers/The Great Mouse Detective