Problem with the hulk is, he's not a hero, nor a villain, it's really hard to portray a good hulk.
If you think hulk was able to control his rage, you're partially wrong....hulk showed various levels of rage in the avengers, andcpersonally i think they did that right...if he was uncontrollable rge, he would have fucked up betty ross as well. So there's your canon. He CAN control his rage, always could, to some extent. Banners deep subconscious can keep things in check for a bit until hulk goes into overdrive.
They did a great job showing his levels of control in the avengers. You treat banner with respect, hulk will be somewhat ok with you ( cap and iron man). You mistreat banner, show you are afraid of him, or trick him in some manner, hulk will try to fuck you up.( hi black widow) you punch hulk, well.....Thor.....
Hulk in his lower level of anger is Banner in some form of control, even in the comics, but as he gets angrier, hulk takes over more and more and eventually becomes a mindless unstoppable force without a known limit.
Trust me on 1 thing, they will never do planet hulk.....never......IF they get a wild hair up their ass and go fuck it let's do it...it will be awesome...but they won't. The story just doen't lend itself to translate well to the big screen for various reasons. Next to some other issues...
Too much hulk, and next to no banner. And yes that is a bad thing.
The illuminati xavier strange richards stark and black bolt agree to shoot him into space.....
Half of those are not marvel property, and you cannot have hero of heroes tony stark make such a decision....not after his buddy moment with banner in the avengers.
No Banner means no Ruffalo, who to me, made Banner work.
Planet hulk fights and nearly killls silver surfer in the arena....not marvel property. In the animated movie he nearly kills beta ray bill, and try to explain that guy to the non comic readers, before you say fuck them, realise that a vast majority of the moviegoers are non comic book readers, aka the reason these movies make money.
This is the big risk they also took with Thor, in that respect they totally nailed it in the first movie....introduce a god of thunder to a non comic reading audience in the marvel universe. And now that that problem is taken care of you can make thor 2 a fun kickass movie.
Those that complain about the "b" team in the avengers movie.....are you fucking kidding me? Who are the A team to you guys then? Ant man? Wasp? Falcon? Vision? I can go on for about 3 paragraphs with avengers that cant even stand in cap's shadow....let alone be called the A team of the avengers.
There's only a few superheroes that fit the bill to be called "A" members of the avengers that were not in the movie. Ms. Marvel, dr. Strange, black panther and luke cage. Luke Cage won't be an avenger anytime soon because you already have a powerhouse with the hulk. Ms. Marvel would be an awesome addition because avengers could use a Few more titties in spandex. Dr. Strange would be awesome....black panther for a bit of racial diversity i guess, but black panthers real strength is his intelligence and you already have 2 super intelligent men in the team.
Now some will say, yeah but i meant hawkeye and black widow being the B listers....not really. Black widow and hawkeye are long serving members of the avengers, and the only 2 next to tony stark ho dont have superpowers. And you need a few muggles to ground the rest of the team a bit...at least for a movie...
In the comics hawkeye is afucking badass, not to mention black widow. Although the goofy arrows can be a bit of a letdown but he hasnt used the really cringeworthy ones in quite a while.