I can't help to think that this poll came about by the posting of my fan story of Spider-Man 4, also having Sandman's role as an important one.
I couldn't find a poll option that suited me...
I think Sandman's story wasn't completed in Spider-Man 3. What happened to Penny? What will happen to the Marko marriage? Will Flint have any troubles with accepting the promise to not raise a sand-hand against the cops? Has he even made that promise?
Having a major Spider-Man 3 villain fly away in a whirlwind of sand isn't good closure...
you know, have a villain leave (but stay in Manhattan) but never show up in Spidey's history again? pfft, yeah right!
No, I'm not saying have him come back as a villain. And no, I wouldn't suggest him come back as a hero. But rather a struggling man trying to save his dying daughter, who has the intentions to do wrong, but is trying to good instead.
Make him a conflicted character instead of a villain or hero.
I would submit that Penny is about to die. Literally, whereas in "3" she was just VERY sick.
Sandman has already made the promise never to hurt the cops, or steal money from the bank again, so now he has been holding secret meetings with Dr. Albert Husch who has been secretly telling him how to go about curing his daughter.
Now Albert, in the past, has mentioned a injectional cure that is suppose to cure her disease, but it is still in the works and at this point could do more harm than good. But now Flint is desperate and he demands the injection. Albert finally gives the unfinished cure to him.
Peter tells Sandman that he'll help in any way possible, and when the cops rise up against Sandman when he's only trying to save his daughter, Spidey helps Sandman against the cops, and now Spidey's name is tainted.
Emma (his wife) finally divorces him and the court makes a law which states that Flint can no longer be within 100 feet of his daughter. Flint is then sent to prison.
Then maybe have him break out of prison when he learns that Penny is seconds from death. He breaks his promise to not hurt the cops to save his daughter, and he takes Penny and brings her to Dr. Albert Husch. On the way the cops shoot Flint in the back with a special gun made to destroy sand. Because of this Flint drops Penny and the fall to the ground kills her. Now it's Flint that has killed her, not the disease. Flint is then sent back to jail.
In the 5th movie, there is an explosion which sets several convicts loose including Flint, Roderick Kingsley and Cletus Kasady.
Roderick discovers the Goblin lair, while running from the cops. He becomes Hobgoblin.
Cletus hides on campus from the cops and becomes Carnage because of the sample given to Connors by Spidey.
Flint hides, but feels indebted to Spider-Man for his help. In a final battle with Carnage, Spidey is about to die when Sandman comes to fight Carnage. A bite from Carnage kills Sandman and the battle continues to an airport, where it leads to a plane which takes off. Spidey and Carnage fight on a FLYING PLANE! Just imagine that!!!
So for 4 he's more like a conflicted character. In 5 he picks up being a hero because of his debt to Peter. In this act he dies. So he'll only be a hero for like 10 minutes in 5...
Now of course Lizard and Kraven will be villains for 4... so Sandman's story for 4 and 5 won't take up too much time...
now this is what I think should be done.