I'm thinking about 4 more games, each featuring a new player and keyblade master, Kiri no Hikari (or just Kiri). The first comes after kh 3D, and it is Kingdom hearts 3 (yeah, i know this is already happening). It is like the big battle to get rid of Xehanort, Xemnas and Ansem once and for all. The next one is called Awakening, and is basically about Kiri and her nobody, Kirameki (or Kira). In the end, something happens and she and her nobody must go into a long sleep to join with each other. So Kiri calls upon Namine, who still lives in Kairi. The end of the game is Kiri and Kirameki joining together. The next game is Believe, where some keyblade wielders, Yen Sid especially, believe that (because of a plan set up by the enemy) Kiri is a traitor. Aqua comes to visit her (as she is locked up) and talks to Kiri, as she is on her side. After that, Kiri escapes into the deep jungle to think about what she could do to prove that she is not a traitor. Eventually she does. The final game, Kingdom hearts 4: The Enemy Within/The final battle. Things are becoming unsettled between the keyblade masters. Riku and Terra are being influenced by the spirits of Ansem/ Xehanort again and turn against the others. Ventus is posessed by Vanitas again too. After disobeying Master Yen Sids orders, Kiri runs off to find Riku and bring him back to his senses. After a long battle, Kiri frees Riku, and with the help of Aqua, Kairi and Sora, restore Terra and Ventus as well.
Sorry that was long