Oh man I dont know if it was just cause I was stoned but WOAH that episode was epic!
I haven't read the manga here is what I reckon is going to go down.
I've never been stoned, but I've developed similar theories to the ones you mentioned.
1. the little pixie leading Zorro around is about to give the mugiwarras heaps of intel on all of Doflamingo's allies including how their powers work.
I don't think its going to be quite that easy. If it was the Straw Hats would probably make quick work of their opponents. While such an outcome would be a good way to show off the evolution of their powers I suspect we'll see the fights drag out just like most fights in the series the same way the Fishman Island and Punk Hazard battles dragged out. I am curious which characters will
! go to assist Nami's group. (Zorro, Sanji, Kinemon, or possibly all three?). I'd prefer it if Nami was able to Jora (the art lady) by herself showing that she is capable of defeating this nuisance herself. However, I don't see how she'd pull it off in her current state, and as we know others seem about to head in her direction to assist her
2. The old guy with the steel cone head, bartolemu, and a fair few other Colosseum pirates are gonna ally when the proverbial hits the fan.
It seems like things are setup that way since no competitors have left the arena yet. (Where even Bellamy whose lurking in the shadows, and said he's a Flamingo supporter may side with Luffy). Its definitely a possibility, but I also think there are a few other possible outcomes when the stuff hits the fan as you say. One: Luffy shows his strength by defeating all of the enemies himself (with others possibly attempting to battle). Two: (more likely) the four block winners end up beating the collective opponents. I don't know who the D block winner will be (I'd guess either Rebecca or Cavendish), but if its Cavendish instead of Rebecca I could see a Luffy and Bartomelo vs Burgess and Cavendish battle first.
3. Zorro is going to fight and defeat the Admiral swordsman.
I think its more likely they'll have a standoff. If Zorro were to easily defeat an Admiral (which I'm sure he's capable of) there isn't many people higher that he'd be able to feud with without him stealing Luffy's opponents. Blackbeard, Akainu, and Mingo all seem like their destine to be Luffy's opponents. I feel like Zorro and Sanji may be stuck at Admiral level opponents for awhile.
4. Do flamingo's power is like spiderman however he uses his web as a weapon and like a puppet master, im still trying to figure out how Luffy will get around it.
Mingo underestimates Luffy, and as Law said that will probably be key in Mingo's fall. Mingo's power seems similar to cloud string, and Luffy's way to battle it may be similar to how one would battle against cloud string. Also just because it could bind parts of Luffy in place I would think he could stretch parts of his body beyond where its being held, and still attack.
5. the toy soldier is rebecca's father
I think that's highly probable as well as the most likely outcome once the toy curse is lifted, but I also think its slightly possible he could be her grandfather (since we never saw what he looked like).
6. there is a devil fruit user on the island who can change humans into toys, Ussop will kick him in the balls.
I can't picture Ussop kicking anyone in the balls. I think Franky would be a more fitting opponent for the toy maker, but I wouldn't be surprised if Usopp gets the credit for the defeat.
7. The Luffy and Do Flamingo Battle is going to be epic
That has yet to be determined - we don't have much to go off on how the two would fight each other. (Other people got involved during the war of the best when it looked like the two might meet, so there isn't much to go off). I could picture Law somehow ending up there (since he has unresolved issues with Mingo), and seeing him and Luffy fight together to take on Mingo.
! Unlimited World Red Battle Colosseum?
8. Rebecca is going to get the flare flare fruit after Luffy takes out the tournament.
I also got that feeling. When Luffy and Franky confronted Mingo's stooge outside the casino/restaurant I thought Luffy might end up consuming it and getting multiple devil fruit powers like Blackbeard which would be fitting in a number of ways. (Getting his brother's powers - which Ace probably would have wanted, and putting him on another level where he'd be more fitting to face both Blackbeard and Akainu). However, since we first met Rebecca its seemed like its meant for her. Although it doesn't seem like it would fit too well with her
! desire not to hurt people taught to her by her mother.
9. there is a long shot that Luffy will intervene in the 4th battle if Rebecca starts losing
I can't picture him intervening. At most I can picture him cheering her on (like he did to Bellamy) with her hearing and that turning the tide of battle.
Man I cant wait until sunday!
I have a feeling you'll be somewhat disappointed as there is no way they'd fit all that in the next episode. It will probably still be a good episode, but like a lot of recent ones you may find yourself thinking: Its over already!?!, and/or I can't wait for the next episode.
I've tried to put spoiler tags around anything that was revealed in this epsiode to keep from spoiling it for people who haven't watched it yet, but if I missed anything - administrators feel free to edit it/add tags.