I could never be upset about it so please, don't flatter yourself.
You're getting into some serious extremely campy territory now ..... training together? Are we going to get an 80's style montage complete with the comeback track "Eye of the Bilchsteim" from the band Survivor??? I think you have the wrong film if you're expecting that. Any kind of training or "team building" will be indirect like you saw with the Helicarrier sequence.
The whole point of the NYC battle was that they finally came together as a team and once again Fury attests that when Earth needs them they will return to fight together.
Campy and cheesy??? Just because Rock Sexton says so, does not make it so.
These individuals are being seen by an agency like SHIELD as Earth's protectors. Not having them train together would be IDIOTIC!
Furthermore, the idea of a
Team training together cannot be campy or cheesy. The execution could be, of course, but if you think it could only ever be cheesy/campy, you show remarkable lack of imagination.
Now if the direction and style of the film doesn't warrant a training scene, I wouldn't have it in there. But I would still think this team (as based on the comic version) would have trained together and wouldn't mind it being alluded to (like you said, indirectly). Imo, the Avengers have definitely not 'trained' together yet. They may have read eachother's vitals (although Stark does mention something like "was I the only one to read the documents") but that's not training (going back to the 'formal team' point of the question).
5th point; Fury's words to Hill at the end made me feel that they would come when they were needed because they were HEROES/Good people. It did not make me think, "because they were a team".
Anyway, I'm done.
PS I never flatter myself. And I wouldn't start here via self-important forum posters...