3) Doc Samson
It’s not one of the film’s major problems, but The Incredible Hulk is guilty of underusing a popular character from the comics: Doc Samson. So much so that fans might have not realized it was him if they had missed his name.
In the movie, Dr. Leonard Samson is a psychiatrist dating Bruce Banner’s true love Betty Ross (sorry Black Widow). In the comics, Samson is also affected by gamma radiation and gains super strength and green hair. And he isn’t really anything like Modern Family’s Ty Burrell, who plays him in Incredible Hulk. Hopefully, the character will make a reappearance in the MCU at some point in the future.
Also, an even more submerged character is a computer nerd who Bruce bribes with pizza to enter a lab. The movie’s novelization confirms that this is Amadeus Cho, an important supporting character in Hulk comics. He even became a version of the Hulk in more recent years.