Marvel's Cinematic Universe

In my study / office there are a lot of comics on the shelves. Mostly European but also a lot of Marvel and some DC comics. Among them the first issue of X-Men Age of Apocalypse, Spider-Man and Punisher. I read them when I was kid. I watched X-Men, Spider-Man, Hulk  and Fantastic Four during Marvel Hour over on the BBC. I now own those same series on DVD, haven’t got around to move forward to Bluray since I don’t see the added value yet. These were my favourite, Captain America and Iron Man not so much. 

I used to love the Incredible Hulk series on tv and when a Hulk movie hit the big screen in 2001 is was looking forward to it very much. When the Incredible Hulk arrived in 2008 starring Edward Norton I was less enthusiastic about, for I did like Eric Bana as The Hulk and Jennifer Connelly as Betty. I think the latter bother me most that Liv Tyler took over that part. This was the same year as Iron Man 1 was released and by that time I had learned that Marvel was working towards an Avengers film and that was why the Hulk had changed in appearance so much. It had to link up with the comics' character. This all is now known as the Three Phases of Marvel, of which we are half way through the second Phase (Phase 1 started with Iron Man and ended with The Avengers film). 
Now six years later I recently read an article on the Business News website that Marvel has planned films all the way up to 2028. That means they are looking beyond their initial Three Phases. Kevin Feige has given some insights in what his thoughts are for the Marvel Cinematic Universe past Phase Three, and it basically comes down that the man a is a visionary (you can read the whole article here).
The thing is, Marvel’s Universe is so vast and includes well over a few 100 characters if not thousands, most of which are unknown to the general public (General Public (salute)). They can tap into a lot of characters. But how long can Marvel keep up with its domination in the cinemas and thus continue all this success? 
Robert Downey Jr. has stated in a recent interview that he thinks is he is becoming too old for playing the Iron Man character, but the thing is he is Iron Man and why people love the films. Just as Chris Evans is Captain America (who also played Human Torch in the Fantastic Four) and Chris Hemsworth is Thor. Casting them was just right, just as Fox has done with Hugh Jackman as Wolverine and he also stated he might be getting a wee bit too old for the character. Keeping these actors is good. People tend to like familiar faces. This is something Sony Pictures didn’t do with Spider-Man.

We had Tobey Maguire in the Sam Rami films and Andrew Garfield in the Marc Webb films, of which part two will be in cinemas this month. In this case it worked out fine and both actors did a great job at playing the character for both series are different in how they portrayed the Spider-Man character. But there's the case of The Hulk and The Incredible Hulk in which the actor change did work for the first two installments (so I think). To me Eric Bana was a great Hulk, Ed Norton not so great. And now we have Mark Ruffalo who nailed it and who will reprise his Hulk in Marvel’s Avengers Age Of Ultron. 
Actor change of a character can work but it can also be an annoyance to fans. The announcement that Ryan Renolds would star as Green Latern to fans was not amusing since he already played Deadpool in X-Men Origins: Wolverine (2009) or the fact that Chris Evans was cast as Captain America some found a betrayal since he already played Human Torch in the Fantastic Four. In this case it actually worked out great and Cap is more loved than ever now with the Winter Soldier in cinemas, which is breaking (as I said before) every  box office record. 
To get back to my question of how Marvel will keep up this cinematic success? Whatever the future holds for Marvel it is imperative that they stay close to the true nature of the characters and their origin stories when introducing new ones to the public. This is something Kevin Feige has done in the past with Thor, Iron Man and Captain America and herein lies the strength of Marvel’s success and as a lover of comics and the films I hope Marvel will continue to do so.