Ehhhhhhhhh not exactly.
Nobody is saying have him hulked out the entire film. He could be placed very strategically.....but obviously that would mean a limited capacity role. In a film with as many heroes as they have, I don't really even think it's that big of an issue if he doesn't have a big role.....just enough to incorporate him.
Then... yes, that is exactly what I said in "A". He's in it just to smash crap then. He's become an extended cameo. He's a nod. He's splashed in. He'd be the hint of mint in a cup of hot co-co. I don't want that.
Even if it's "smart Hulk" it'd just be him going "Sup guys? Watch me punch stuff!" -smashes- "Laterz!"
If he's "strategically" placed with a limited role, I say don't do it. If you are going to give him or anyone else nothing more than a bit part, leave him them the **** out. This is an Avengers film, as such, each Avenger should be highlighted and move the plot along. This should be about their interactions with each other.
If they can't do that balancing act, then I say cut down on the number of Avengers. There are too many fans for each of these characters for anyone to end up with too a limited role... strategically placed or not.
And the Pym's will be his paperclip collection. 
)
Let's not forget Ave... Hulk does tend to get shafted quite a bit when it comes to movies. Whether at the Box Office, the fans, the general publics receptions of his films, or heck, his parent company caring so much about him they signed on Zak Penn to write his movie, and then cut out most of the character development... nice.