Even if they were never actually gone, you can't keep playing that same card (whether it be for 2 seconds or 2 movies) and think that it will be fresh or get the desired response. We already have seen Stark "die" twice. In 2 straight films no less. Doing it again won't be original. Nor do I feel it is necessary either. People only are discussing this or wanting this because of Whedon's rep as a writer, not for an legitimate story related reason. These discussions are just funny to me, given I have followed Whedon for years, and in all those years, he hasn't been nearly as kill happy to main characters as people think he is.
If people want characters to die, wait for Avengers 3. The film that will feel more like a finale (and will be in many ways). Don't waste your best cards at the mid-point of the story. You want a tear jerker? Kill Fury, Hawkeye, etc. That will get the desired effect. We don't need one of the major Avengers to "die."
NO......Don't kill Hawk Guy