It is incontrovertibly known that bringing Gwen Stacy into this series this late was a huge mistake, one that could not be successful no matter how hard they could even try. Gwen is a now or never choice. In Part 1, Raimi chose to use MJ as the girlfriend, thus placing Stacy into the 'never' category. Years later, Raimi and the studio decide to backtrack and change their mind, now wanting Gwen. It seems to be like they only brought her in to please the comic book fans. No one else would possibly have cared if she wasn't in this film.
Peter Parker was suppose to love Gwen Stacy in part 1. Completely fall head over heels for her. Her death would mean just as much to him as Uncle Ben's. But let's look at the convoluted web we're stuck in now. In The Spider-Man universe according to the gospel of Raimi and Arad, MJ is the only girl Peter has ever loved. Once they break up, he still loves her, and he wants her back. So Peter simply meets this blonde girl named Gwen Stacy and takes her to a jazz club one night just to make MJ jealous.
Where does Gwen Stacy honestly come into the story as of this series? What could they possibly do with her? Kill her off? It won't even be by the Goblin, and would the death of one character that Peter has known for only a few weeks and doesn't even love, really going to affect him? They can kill her off, but there's not a single bit of emotional investment in the character so it means nothing. They can keep her living in the series, but it completely defeats the purpose that is "Gwen Stacy."
As I said, Stacy is a now or never choice. In 2002, they didn't introduce her, so they never should have.