A few comic book movie tropes are starting to fade-away, cheesy one-liners, horrible costumes and poorly done special effects. When it comes to revealing new heroes, we tend to see the classic "origin story" used. The main hero is normal (usually the first act or 20-30s of the film), but undergoes a massive transformation that finally gives us the hero in-action.
Marvel has been known to overlook this recent origin trope, by using exposition and flashbacks. We first saw this with the interesting flashbacks used in the opening sequence for The Incredible Hulk. Instead of rehashing Bruce Banner's origin in the reboot, we see him already on-the-run and hiding-out in Brazil. We kind of also saw this with Thor, as the god of thunder had previous adventures and is already wielding mjolnir. Again, this was done extremely well with Guardians as the trouble-makers were are already causing problems in the galaxy, just not as a group. Leaving a little mystery to the origins of our characters isn't always a bad thing, either.
According to Devin of BadassDigest, Marvel is finished with origin stories. This will likely effect Ant-Man as well, which will have the established hero (Pym) played by Michael Douglas hand-over the mantle to Scott Lang (Paul Rudd). A great way to skip a bulk of the movie just setting-up sequels (where we see the hero in full-form) and the final action piece.
He goes on to mention that we'll see Stephen Strange already the Sorcerer Supreme in Doctor Strange and that we won't have to spend a large portion of the film without him playing the hero. Along with screenwriter Jon Spaihts' (Prometheus) extensive page-one rewrite of the entire script. Meaning, that the original draft that was circling a while back, is getting completely scrapped from the project.
We still haven't had Marvel announce who will actually play our Stephen Strange. The actors who are reportedly in the mix include Benedict Cumberbatch (seemingly out of the running because of a play in London), Tom Hardy (Mad Max Fury Road, Dark Knight Rises, Inception, Bronson, Warrior, The Drop), Oscar winner Jared Leto (Dallas Buyers Club, Fight Club, Lord of War, Requiem For A Dream, American Psycho) and more recently three-time Oscar nominated actor Joaquin Phoenix (Gladiator, Her, The Immigrant, The Master, Inherent Vice, Walk The Line). I'm personally rooting for Hardy and Phoenix to get the role, since they have an extremely strong body of work.
The production start of Doctor Strange will begin in Spring 2015, with a release date of July 8th, 2016. Casting announcements are bound to begin very soon, as pre-production starts ramping-up.