The ending.
I don't have a problem with sad/bittersweet endings. It's just that this movie wasn't really building up to that. His death was revealed to us the audience in such a sudden way. We didn't even see 5 minutes of him and his new girlfriend. And it kinda goes against the rest of the movie, which is so light in tone. Really, would the real MARK want us to leave the theatre without a smile on our faces?
I think the movie should've opened with his funeral, then go back and tell the whole movie exactly how it was, and end with his funeral again but on a more positive note.
Thoughts?