Okay, that's it. This ending, and KH3D's Trailer blew my mind. I just had to make an account here for that .-.
Anyway, i got a few theories. Since Aqua spent the whole 11 (10(Kh1) + 1(Kh2)) years in the RoD, it wouldn't be strange at all for mickey to arrive there at some point. Don't forget he went to the RoD BEFORE he met Sora after the battle with Ansem SoD. So that would explain he's using Star Seeker instead of Kingdom D.
And since Malifecent went to collect the princesses of heart somewhere before Kh1, it wouldn't be that far fetched to see Aqua ending up in the Castle of Dreams, now taken by darkness. As for Sora and Ven dissapearing, no clue. Probably foreshadowing.
So:
-BBS takes place.
-Aqua goes to RoD
-Aqua sees the darkness spreading into the RoL, either due to AX's experiments (the Artificial Heartless have to come from SOMEWHERE, right?) or due to Sora completing Hollow Bastions Keyhole in Kh1 (It implied hundreds, if not thousands of Heartless leaked into the RoL due to that.)
-Secret Episode is played, and the mysterious Red-Eyed enemy is fought.
-Castle of Dreams is taken by darkness, where Aqua arrives an unspecified time later.
-King Mickey, noticing the dissapearing worlds, goes to the RoD to investigate.
-KH1 takes place.
-King Mickey finds the Kingdom D, and later helps Sora close the door to the RoD.
-(Theory) King Mickey meets Aqua at some point (hinted at in Re:Coded's secret ending, they imply Aqua's been located)
-They split up, Mickey joins with Riku, and they head of to CO.
-KH:CoM takes place.
-During Kh
ays, DiZ puts the data Naminé told us about inside Sora.
-Kh2 takes place.
-Aqua meets DiZ at the RoD
-KH:Coded takes place.
-Sora and Co. recieve the letter from King Mickey.
-Sora and Riku set off for the MoM test, thus KH3D takes place.
-(Theory)WHILE Sora and Riku are off at the MoM test, Kairi is lead to the mansion by Naminé, who's now "residing" in her.
In other words, this is a giant recap of the series disguised as a new entry. Hope it's either PsP or 3DS. No PSP2 pleash D: