Before I get started I'd just like to say I LOVE the MCU, but the sad part is it wont last forever. Here's my prediction of what will happen in Phase 3 with possible tidbits for the future of the MCU.
Recently Kevin Feige stated that he wants Avengers 3 to be 3 years after Age of Ultron, if that were true it'd be cutting the MCU shorter than most of us expected and would like (lets be honest). I don't think Kevin Feige will cut his cash train short, it makes sense that he'll want to extend the release of Avengers 3 (when a lot of contracts are up) out as far as he can so he can build the universe more while also building it for the future.
There are a few dates for phase 3 that have films already attached to them, lets take a look:
Phase 3 - So far
July 17th 2015 - Antman (Confirmed)
May 6th 2016 - Captain America 3 (Confirmed)
July 8th 2016 - Dr.Strange (Rumor)
May 5th 2017 -
July 28th 2017 - Guardians of the Galaxy 2 (Confirmed)
November 3rd 2017 -
May 4th 2018 -
July 6th 2018 -
November 2nd 2018 -
May 3rd 2019 -
Notice any patterns just off of this information? Antman (A new property) is being released only a month after Avengers: Age of Ultron is released and will likely still be in theaters. We see the same pattern with Dr.Strange and Captain America 3, this is a very smart move by Kevin Feige with each of his established franchises acting as a security blanket financially for their new properties.
With Guardians of the Galaxy now officially a hit, it's pretty safe to say that GOTG2 will be paired with a new Marvel property. (Black Panther anyone?)
Here's my official business/money making/safe prediction for the rest of phase 3 and into phase 4.
May 5th 2017 - With Kevin Feige's recent comments about Black Panther and Wakanda rumors, I think this date will safely belong to Black Panther, with GOTG2 being released a month later and riding the momentum of the first film.
November 3rd 2017 - Marvel will close out its 2017 slate with a new property (Surprise!) I can hear angry keyboards typing away screaming for Thor 3 but hear me out. Chris Hemsworth recently said Thor 3 is "A ways away". Now Thor: The Dark World was good...but that's it..just good. Captain America and Guardians of the Galaxy are on a different level filmwise. I think Marvel will take their time developing Thor 3 so that it can be the best Thor film we've seen. I think this film may be a new property, possibly Inhumans (I'm not too familiar with them, but I've read interviews and everyone seems to think this movie will happen) or Captain/Ms.Marvel
May 4th 2018 - Here's another surprise to some, many have speculated that this will be Avengers 3, it's too soon. DC is ramping up their plans, I dont think Marvel will spend all their big players right when DC is catching fire with Justice League. I think this is the spot for a new Hulk film (whether he be in space, Earth, etc.) but that's not all, I think this will be a team-up movie of some kind for Hulk. Not with Ironman like many people want, but with either Guardians/or Captain Marvel (if hulk is launched into space) or Antman. Why Ant-man? Ant-Man is one of the riskier properties Marvel has, not because of the character, per say, but because of his name. When I've talked to people about Antman, they laugh thinking I'm joking, Ant-man may not be a hit, if it ISNT i bet they'll do a team up film simply because of timing. It would be 10 years since a solo-hulk film, and 3 years after Antman has been released, if they wait until phase 4 for an antman 2 providing it's a hit, it would have been at least 4-5 years for a sequel, that's a LONG time. Alot of people would pay good money to see a team up film from Marvel, something that ISN'T the Avengers, and featuring only 3 heroes.
July 6th 2018 - This is the where we get our Thor 3, this and my previous movie prediction could swap spots, however after seeing GOTG one thing became apparent to me but also started to bug me. The infinity stones seem to keep distancing themselves for Thanos and frankly, he needs a win IN SOME FORM. This will tie in nicely with Thor 3, now that Loki has killed Odin, Ragnorok will ensue and I think this is where we'll get our Echantress and maybe AT LEAST an explanation of the Infinity Gauntlet and what it does. I'm not saying this will be the main story, but maybe an after-credits scene with Loki and Thanos or Echantress and Thanos etc. Imagine if the plan Loki had THE ENTIRE TIME after Avengers 1 was to simply gain access to the infinity Gauntlet to Thanos could access it. Imagine seeing that after the credits or right before the credits roll. Thanos gets his Gauntlet, major cliff hanger further tying Avengers and Guardiands together (Sadly, most the people I've talked to dont even know these movies are linked in the same world).
November 2nd 2018 & May 3rd 2019 - Keeping with Kevin saying he wanted a third Avengers film 3 years after the 2nd, I believe that they will end up splitting Avengers 3 into two separate parts. I recently read the Infinity Gauntlet story arc, I don't think they'll keep it EXACT but pretty close, and you simply CAN'T put that much story into one film, so why not split it in two parts and get the most out of your actors contracts (Reminder, a few expire after this film). This is also a perfect place to tie Guardians with the Avengers. Part 1 would deal with the Guardians battling Thanos and him conquering Xander to recover the Power Stone, Thanos would learn that Star-Lord is from Earth some how, and makes the connection with his previous defeat at the hands of the Avengers. Star-Lord and the Guardians would then head to Earth to warn the planet on the impending attack and the danger Thanos is. They meet, maybe fight, explain their intentions, etc. Part 1 will likely end with a big cliff hanger, then it will be the big finale. I also think Captain America will die in this film.
One thing I've noticed is how many people haven't come up with ways for Ant-man, Black Panther and Dr.Strange join the Avengers. With the team up film, this is how multiple heroes can meet each other etc. Black Panther I imagine will be introduced in Cap 3 or Avengers 2.
The Future.
With Phase 3 ended what will the Avengers roster look like now?
This is alot easier than some think, some of the current Avengers will remain intact simply because of their contract length (Ruffalo, Stan) while others will leave (Evans, Downey Jr, Hemsworth) and new ones will be introduced (Antman, Dr.Strange, Black Panther) I think the new Avenger roster will look something like this, I don't think Tony Stark will die, but his presence will still be felt much like Cap 2, Incredible Hulk, Thor (Name drops, tech drops, etc.)
Hulk (Ruffalo)
Dr.Strange
Black Panther
Captain America (Bucky version)
Antman
Falcon, War Machine, Hawkeye*(I could see this being any of these three)
Thanks for reading,
Go Marvel