Shane Black is justly well-known for putting a self-referential spin on worn genre cliches to come up with something that gets to have its cake and eat it: it benefits from the familiarity and shorthand nature of these tropes, while also sending them up. Nowhere is that impulse better illustrated than in the Tennessee segment of "Iron Man 3" in which Stark teams up with angel-faced urchin Harley. What threatens to become an obviously manipulative, irritating diversion from People Falling Out Of Things That Are Blowing Up, is pulled back from that brink time and again, by a black hearted one-liner from Stark or a deliberately annoying, un-cute moment from Ty Simpkins (who did a surprisingly non-cloying version of "precocious kid"). Yes they bond in the end, and yes the kid gets the ultimate Extreme Shed Makeover, but there's been just enough "I am not your father" sourness along the way for that not to grate too much.
As much as some of the more diehard fans are up in arms over the totally non-canon way The Mandarin is portrayed here (and it does open up some interesting questions about future potential Iron Man villains if, despite protestations, they do come back for a fourth outing), we can't really complain about this major character getting short shrift if only because, written as it is, it gives Ben Kingsley a chance to flex his fun muscles. His Trevor Slattery is a brilliant creation, and if his cluelessness is clearly an impossible front to maintain (he did, after all, shoot a guy in the head on live TV), the portrayal is just sly enough, as well as being outright funny, that it gives a sinister edge to what could otherwise just be a patsy. And the character reveal of him coming out of the toilet was one of the best-done twist moments we've seen; he adds a layer of loopy comedy that plays well as distinct from Stark's quickfire quippy wit. So even though we've got big issues with the architecture of the villain plot (see "Worst"), on aggregate we'll take it if it gives us a performance as enjoyable as this one.
Tony and Pepper's relationship has gently subverted the typical hero/girl Friday model throughout the series, but it's at its most interesting here. Where usually there's some element of rivalry or will they/won't they suspense, here they're in love, they're together and what they're struggling to do is maintain a mature and mutually fulfilling relationship. Not exactly sexy on paper, but the stars make it so, and give the emotional core of the film a kind of wisdom that is refreshing for a comic-based movie aimed primarily at teenage boys. And it's not just Pepper and Tony, but Rebecca Hall's Maya Hansen (despite the major problems there, see below) runs counter to what we might expect in this regard too. After one night with Stark, she's not desperately in love with him and the way her arc plays out is less the old Bond routine of the bad girl being made over by love and self-sacrificing at the last minute, and more about her coming to a realization about herself and where her own moral compass has broken down. She's not a well-drawn character by any means, but at least she's not a bit of fluff, and the awkward "girl I had a one-night stand with meeting my long-term girlfriend" moment is nicely mined for its comic potential, but not over-egged into being something more important than it is.
Maybe our biggest gripe about the film, and one that bleeds into other points covered in this "worst" section, was the lack of a defined and memorable arch-villain. Guy Pearce is as reliable as ever in the role of Aldrich Killian, but he's simply not given clear enough motivation or clear enough goals for him to be a truly interesting, worthy adversary to Stark, and with Maya Hansen eliminated relatively early, and The Mandarin revealed to be a stooge, there exists something of a vacuum at the "evil" end of the good/evil spectrum. As much as we enjoyed the opportunity it gave Kingsley to bring us the gonzo entertainment of Trevor Slattery, the fact is that the Big Bad being a guy ultimately motivated by a ruthless but straightforward desire for power is just not as scary as the idea of a terrorist motivated by some arcane and unstoppable whacked-out ideology. What is it that Killian wants exactly? What is his endgame? To control the U.S. government via a proxy President and also have a mouthpiece terrorist at his disposal so he controls both sides of the equation, right, but well, why? What's in it for him? If he's supposed to be a crazy-mirror-image of Stark, right down to his genius and his attractive sidekick, we should also have a similar idea of what it is he needs to achieve and why -- and revenge on Stark for standing him up a decade ago doesn't really cut it.
We love us some Rebecca Hall, and this is not to say there aren't some good moments featuring her character (see "Best") but Maya Hansen here does very little except have a one night stand with Stark back in the day, and then inexplicably show up at his house with the idea of what, exactly? If it's to persuade him to help them stop the unfortunate "exploding" side-effect, why so late in the game, and why does she immediately flip back to Killian's side, especially if it's just to get instantly killed (and if that, we haven't spent enough time with her for that to be a real loss)? Also, she's so brilliant she developed Extremis, but in a decade has never been able to figure out the equation Stark scrawled drunkenly on the back of that note after looking at her research for about 5 pre-nookie minutes? To say nothing of not being able to work out that Killian having a hold over the Stark (in the form of Pepper being tortured) means he doesn't really need her any more? Having your hero be richer, morally stronger, more successful and infinitely smarter in every area of expertise than your bad guys doesn't necessarily increase him, it simply diminishes the stakes.