Bring on Edgar Wright! I think he'd be a great choice to direct "Iron Man 3". Also @Admrial2 Joss has given interviews in the past about his experiences on "Alien:Resurrection" and has pretty much asked for forgiveness and dismissed it, his problems with the studio have been well documented as was pointed out earlier. Much like his writing experience on "Titan A.E."
I seriously doubt that Favs would want to reprise his role as Happy Hogan if he wasn't directing. I have a feeling his departure was not on good terms.