These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
They Wasted a Perfectly Good Plot: After The Avengers, a team up between Iron Man and Hulk sounds like a great opportunity for Tony Stark and Bruce Banner to banter with each other and use science to save the day. This opportunity became wasted due to Hulk never changing back to Bruce in the movie. Under Jeph Loeb, Marvel Animation runs under the assumption that kids find Bruce boring.
Most reviews state that even if you don't mind Hulk never turning into Bruce, the script still seems too juvenile and the animation too shoddy for this movie to appeal to anyone other than the least critical of the youngest Marvel fans.