Totally agree, the film was awful. Worst than Iron Man 2.
Admittedly RDJ brings some comedy to the role, and Ben Kingsley as the Mandarin was the best thing about the film. But just poor script writing for the main story with a plot devoid of logic.
Bit I probably hated the most was when Gwenith Powtrow gets 'Extremis power' and saves Tony by doing a somersault kick or whatever that was. Subsequently she's bewildered by accomplishing such a feat.
The problem with Iron Man 3 is lack of rules. For example, the bad guy, Guy Pierce is imploded or whatever by the Iron Man Mark 47 (or whatever) suit. Somehow he survives being blown to bits and regenerates good as new. If the script writers don't have rules to construct the world within, it becomes a free for all. Anything can happen without logical explanation. Which is actually what happened.
Film was too long with too many bits that didn't contain Tony as Iron Man or Rhody as Iron Patriot. I think the problem is that their trying to hard to construct these films to fit with the Avengers, rather than making these films individual units that can stand on their own merits.
Not sure how this film made so much money so quickly when the second one wasn't good, I know 3D has something to do with it, but still. Man of Steel should hopefully be a lot better.