Dream Drop Distance KH3(or Kingdom Hearts: Reconnect) theory based around 3D (Spoilers present)

Hi, I'm actually a returning user, and for all I know, my original account was destroyed. But I have come back with an idea; also, prepare, wall of text commencing.

After a year or so of not really caring about the KH series, the secret ending in Re:Coded and the Dream Drop Distance trailer have sparked a new interest in me. Now I'm more than aware everyone here is quite pissed at the prospect that it's been 5 years since a console release of Kingdom Hearts 3, but at least we know the plot right?

All the side games (With the exception of 358) released recently have laid it all out for us.
What we know is that KH3 will involve:
1. The ultimate defeat of Master Xehanort, and
2. The revival of Terra, Aqua and Ven(and maybe Roxas, Xion, Axel and Namine?). Right?

From the secret ending of re:coded, we know that Sora and Riku are off to complete the Mark of Mastery exam before finding these characters. From what I've gathered, 3D will mostly take place in a dream-like state so that they can complete their training in a short amount of time; sort of like the hyperbolic time chamber in DBZ. Except, it'll some how involve a digital version of those pods that Namine is so famous for. It'll most likely explore the memories of Sora and Riku and have them face stronger challenges all the while improving their moves and techniques, hence the much more impressive moves demonstrated in the trailer. The "drop" part of the title, as mentioned in the trailer and Nomura interview, serving as a reference for Sora and Riku "dropping" into an assortment of challenges. Such as 1:04 of the trailer, which shows Sora "dropping" into a memory of Riku's, and 1:43, which shows Sora "dropping" into Twilight Town.

And here is where my idea takes hold. In all of Dream Drop Distance, they're working simultaneously, correct? They're BOTH improving, TOGETHER so that they may face Xehanort TOGETHER which brings me back to KH3.
With the abundance of keyblade masters being thrown into the game, it's obvious that Sora will be working with a lot of help. From here, it can go in one of many ways, but one idea keeps coming back to me.
It's possible that the game will go on as usual, where you occupy the game as Sora, playing through all the levels with Donald and Goofy and the occasional extra member, or in other words, the same formula from the other main titles. However, all games released after II have tried hard to separate themselves from their console counterparts. Each one deviating just slightly from the original control scheme.
1. 358/2 - The first in the "New" handheld series. The control scheme is mostly unchanged, but the panel leveling was the first big difference. Also, on a sidenote, it was the first to include multiplayer co op.
2. Birth by Sleep - Huge change in gamplay. Introduced multiple story lines, D-links, Command Boards, Shot locks, etc, all while maintaining a similar combat formula. Again, this game features a multiplayer mode for co op.
3. Re:Coded - Still only recently released, this game has an almost amalgamation in gamplay mechanics. It controls a lot like 358, but contains some traits from Birth by Sleep. No co op multiplayer, but some online capabilities.
4. 3D - (Keep in mind, that this is all speculation based off the trailer and interview) Nomura stated in his interview that there will be a new control scheme, one each for Sora and Riku, respectively. Since it's for 3DS, it'll most likely have a control scheme similar to Birth By Sleep, since they each have the same number of buttons. Multiplayer will most likely be included for co op as well, since the story involves both Sora and Riku working towards a common goal.
Of course, you also have to remember that these control schemes were made to accommodate for the number of buttons on their respective handhelds, but a lot of the new features were met with high praise and it wouldn't be too blasphemous to have a spiritual successor to these panel systems in the next console release. Also, with multiplayer included in every new game, what reason would they have to not include some multiplayer aspect to KH3?

If you've actually read to this point, I congratulate you, but you're probably wondering what point I'm trying to make from this. My ultimate hypothesis presented from the all the gathered data is that KH 3 will feature a co op campaign.
I am more than sure that there will still be a single player story mode featuring exclusively Sora, but for what reason would they have to not feature a co op option?
It's safe to say that 3D will be a single player venture, given the capabilities of the 3DS and the nature of the story, but if KH3 works out the way it seems from all the secret endings, Sora and Riku will embark on this journey together to both defeat Xehanort.

Now you're probably wondering, "But Jose, what are Donald and Goofy going to do? And what about Nomura's constant trend of separating the main character from the rest of his team?"
Well,

A. Think about it. If Sora and Riku needed to go on some spectacular test in order to defeat Xehanort, would Mickey really trust sending Goofy and Donald into that kind of danger? In all the games prior, the team acknowledges that Sora is far stronger than the two of them, and Riku is definitely on par with Sora. Now, if this new enemy is so powerful that the two of them combined isn't strong enough to defeat him, then do you really think Donald and Goofy would play well in the situation? In fact, if this theory is fully supported, Donald and Goofy may not even be involved in any actual game play, but I seriously doubt that will be the case. Besides, KH is quite the fan service. I think there are a number of people who would proudly support a Sora and Riku centered story.
B. At one point in the story, Sora and Riku probably will have to take two different roads, but how many keyblade wielders are we aware of? With Terra, and Aqua now involved, they could be re-woken in some part of the story, allowing for the continued "dual" keyblade aesthetic. Not to mention, Mickey will probably play a much larger role in this story, and even if the co op idea is not made to fruition, Sora, Riku and Mickey is a very potential team(In fact, in the secret ending to Re:Coded, Mickey states word for word "Me and Sora, we'll be ready. And Riku, too.").And lastly, Nomura is not one to follow his own rules (i.e. The "one" keyblade wielder), so the possible reincarnation of Axel, Namine, and maybe even Roxas and Xion, in one form or another, is not horrifically unlikely.

C. This is just my own personal reason for the co op inclusion and the omission of Donald and Goofy. Overall, I think it just sounds like a really interesting and exciting idea for the KH series. For the last few years since 2008, we've been presented a huge multifaceted story and deviated titles. We've been introduced to a slew of new characters and side plots. And the gamplay mechanics has had breath after breath of fresh air blown into the games to keep things exciting.
Like I previously stated, Kingdom Hearts is a crowd pleaser. I can still picture an overall ending having all the currently existing Keyblade wielders come together to defeat darkness as a whole, one spectacular(and hopefully difficult) boss battle that can happily wrap the series in one neat package. Granted, the amount of money these games rake in can ensure Kingdom Hearts games for another few years, we can at least hope that the "Epic of Sora," "Epic of Xehanort," or whatever you decide to call it, can end with a very fulfilling trilogy.

Biblio. Here are the sources I used(besides my own experience) to formulate this idea.
If there's anything that contrasts my idea, please let me know. Hopefully we can work out enough of the story to have a decent grasp on KH3.
http://kingdomhearts.wikia.com/wiki/Kingdom_Hearts
http://kingdomhearts.wikia.com/wiki/Kingdom_Hearts_Birth_by_Sleep
http://kingdomhearts.wikia.com/wiki/358/2_Days
http://kingdomhearts.wikia.com/wiki/Kingdom_Hearts_Re:coded
http://kingdomhearts.wikia.com/wiki/Kingdom_Hearts_3D:_Dream_Drop_Distance
http://www.kh-vids.net/showthread.php?109271-KH3D-Interview-with-Nomura!

And of course, the secret endings and trailer:
Birth by Sleep:
http://www.youtube.com/watch?v=zYNnogO-DJI
Re:Coded:
http://www.youtube.com/watch?v=RGyvigmtLgc
3D trailer:
http://www.youtube.com/watch?v=Q6rSwB2MdUE

 

I agree with you also, on some things, overall I personally think that Sora and Riku will be separated to see what they can find on their own, I think Mickey would go with Riku and Donald and Goofy would go with Sora, I mean come on, whats a KH console game without the trio together?