Your posts are hard to read.
Anyway, him drinking because of competition?

Da fuck. Shit makes no sense. The Demon in the bottle storyline hasn't been worked into the movie yet, that has to take time, it's a storyline that has to come later in the life of Tony Stark and become really his biggest enemy. You can't put Tony's biggest enemy in the 2nd movie.
In the first movie it was guilt, 2nd movie it was everything crumbling around him + having to deal with a villain who wasn't his responsibility in the first place. Movie was vehicle son - father relationship, his selfish and individualistic attitude pushing his closest friends away, and for a more comic like feel to it with the introduction of the Avengers.
I just don't see anything wrong with it aside from it still being a feel good movie first that at the end of the day is like Tony Stark, a crowd pleaser. Which it is.
Because i go to the cinema plenty, and i can count with the fingers of my hand how many times i head the audience laugh and applaud during a movie. It works.
For comparison, Transformers 2 was silent as shit.