REGISTER TO REMOVE ADS
Welcome to KHI!!
And as for your question, no one should succeed Sora.
Also, Aqua isn't existing when Sora is alive, so he couldn't.
Riku had his own little miniquest,so it could work. With a little work on the side.
Lolz, Aqua isn`t in Sora`s time. (no she won`t return) Also, they should end the series with Sora, not add another main character.