I bet most people here aren't aware that this movie is based on a novel. The novel is extremely funny in a satirical sort of way, and isn't uplifting or schmaltzy. It is much more a criticism of America than a love letter to it. But I understand why they made the film like this, a movie that was more faithful to the book wouldn't do nearly so well at the box office.
From what I hear, the movie is much better than the book... You can take a look at the book reviews at Amazon and they all seem to say that the movie was much better.
http://www.amazon.com/Forrest-Gump-Winston-Groom/dp/0743453255/ref=sr_1_1?ie=UTF8&qid=1346811243&sr=8-1&keywords=forrest+gump+book