3. Keeping Pepper Potts Alive (Iron Man 3)
Prior to its release, one major expectation of Iron Man 3 was that either Pepper Potts or Happy Hogan would die, and given how much Pepper means to Tony, it seemed fair to assume that it would be her. After all, what better way is there to cement a villain than to have them murder the hero's love? However, Shane Black basically wimped out at the last minute, having Pepper be dropped into a smoldering fire, only to survive because of the Extremis virus she was infected with. If Pepper had instead been killed in The Mandarin's attack on Tony's home, it would have accentuated the gritty tone Black was shooting for, and also made Tony's quest for revenge that much more poignant. Instead, it really comes down to the bad guy blowing up his house and putting the comic relief sidekick in hospital, which isn't fantastic motivation for an epic action film like this. I can see why they didn't kill Pepper off, but it would have helped keep things interesting, and no doubt left us a very different Tony Stark for The Avengers 2.