1.The "broken promises" thing in the end. Terrible idea and spits in the face of the semblance of a theme they were trying to create.
2.Ratha. The most obvious victim of the editing.
3.Curt Connors being basivally what Ock should've been (and vice versa). Ifhans got the shaft big time.
4.The fact that the Lizard was talking to Connors. 2002 called, wants the idea back.
5.The Lizard was uninteresting and they dropped the ball by not having his family be a big part of his character and arc.
6.They started small and went too epic disproportionatelly. Again, the climax should've involved a devoid of humanity Lizard attacking his family. Would've tied the themes of the movie much more. If they were gonna take cues from GG for Lizard, they should've at least taken the right ones.
7.The SWAT Lizards being almost a non-issue.
8.The clumsy way they tried to show how Stacy was obsessed with Spidey. With a line that was spoken without directly showing his face, too (which means thery could've cut it easily): The Lizard is destroying everything, but when he learns about a sighting of Spidey, he goes after HIM? Wow.
9.The cranes. God dmanit, I can bash that scene for hours. While not as cheesy in presentation as is SM1 equivalent, at least the latter had some setup, and that scene was the payoff. Here, the crane operator somehow deducts that Spidey needs this particular kind of help, assembles his co-workers in 5' (that, or the Lizard is the slowest comc book villain ever) and do this whole thing. It's cheesy AND a plot hole. Terrible, perhaps my most hated part of the movie. Sony will NEVER learn.