Inventor
Tony is brilliant, but where his intelligence truly shines is in the realm of engineering and robotics. He can create things that appear as magical to the mundane out of what amounts to common household items and is almost always doing testing on the next big thing. He has entire divisions of Stark Industries assigned to research, but ultimately he is the deciding force in what does and does not become prototyped.
Technological Sciences
Tony's knowledge in various Technological sciences mirrors his knowledge of the Engineering sciences. Indeed, in many cases they do tend to work hand in hand - allowing his ability to combine elements to solve problems, and apply soluations to be that much more effective and exponential in number.
Business Acumen
Tony got his MBA from Harvard almost as an afterthought following his time at MIT. But he figured if he were set to be Stark Industries next CEO he should know something useful about business. It is by far his least favorite thing but it doesn't make him any less a shark in the boardroom. Many of those who have sat across from Tony in a boardroom have commented that they would rather chew their own arm off than have to deal with him on a regular basis.
Charm
It's a Stark trait, really. Stark men are notoriously charming, whether they're seducing women or wrangling a board room. Tony uses that charm to great effect, often pulling magical business deals out of his hat at the last second or managing to, somehow, come out ahead of the curve on almost every endeavour he puts his full mind to.
Technomancer
While he has no particular magical ability and certainly doesn't manifest any direct control over technology, people have started to wonder if perhaps he's not, himself, a mutant. He's not, he just understands machines on a viceral level. It's something on which he can always put all of his mind, the next great frontier. Which is one of the reasons that Stark Industries is the cream of the technology world and spoken in conjunction with several high profile patents that have net the company billions.
Stark Industries
Stark Industries, Tony's family business, is a Global technological powerhouse. Since shutting down the weapons divisoon, has branched out into dozens of technological directions. Think of a company that combines the best of Apple, Microsoft, Oracle, Google, and Amazon. It's kinda like that.
Iron Man
Tony's Iron Man invention is a global game changer. Infinitely configurable and customizeable, Tony is taking a Swiss Army Knife approach to the refining, development, and application of his invention. There is one version of the suit that is a default, with customizeable loadouts and modular packages that can be included. There are also several other versions in various states of development, testing, or available for use.
Personal Fortune
Tony's own personal fortune, minus what he gets from his ridiculous Stark salary, stock options, bonuses, etc would make him one of the richest men in the world alone. His ability to make his money make money for him will keep him that way for several lifetimes to come.
Jarvis
JARVIS is Tony's own designed AI. He's responsible for handling many of the mundane aspects of Tony's life and acts as an ersatz butler, a one stop library of Alexandria, debugger of new software and inventions, and now as a co-pilot. JARVIS is always on board in Tony's armors and keeps a monitor of all operational aspects of the suits in addition to calling out and acting as damage control. If he calcuates a dangerous sitation he can also take control of the suit to provide telemtry and flight path to get Tony out of trouble. This gives the appearance that Tony's reflexes and precision are much higher than they really are - something that both Tony and JARVIS are comofortable with. Not just anyone can boss JARVIS around though - the only one with a command level on par with Tony's is Pepper, and even she's not given full access to JARVIS' command matrix.
Reputation
Even if Tony weren't a billionaire he's made a good use of his family name by establishing contacts with other business firms. He's world reknowned and something of a celebrity outside the business world as well, carefully manipulating the media to make himself something as close to a household name as he possibly can without actually starring in any television or movies, though he has had offers.
Futurist
Tony is thinking on or beyond the cutting edge. So much so that out of the box is often an obsolete concept to him. His ability to build current things with future, undeveloped innovations keeps him two steps ahead of anybody, and if those innvations are too slow to come about for his liking he might whip something up just for fun.
Genius
Tony's IQ and ability to think, reason, learn, and comprehend are almost off the charts. He's considered one of the top five minds on the planet, and rightfully so. It's this single gift alone that has allowed him to be able to do all of the things he can do.
Idealistic
Tony is an idealist. He sees a world that isn't how it should be yet, but is getting there, and he sees how he can help it get there even if he has to lead it kicking and screaming. It might mean he does the wrong thing, but it's always because it's for the right reason, and his heart is in the right place.
Accelerated Learning
Tony's genius comes with a gift. The ability to learn at an exponential rate. This applies to furthering his knowledge of fields he already knows, or delving into and becoming an expert in entirely new ones - take, thermonuclear astrophysics, for example - literally overnight.
Playboy
Tony is a playboy, which is what happens when really smart rich guys get bored. It leads to many things, such as Tony being one flaky son of a bitch. He might be late, or miss a meeting outright and because he is who he is people will switch to "Tony Time" accordingly and his schedule becomes theirs. This might mean he's not where he should be or running late because he's mastering something he just started learning the night before, got a bug up his ass and went to experience the nightlife in a city half a world away, wanted to shoot craps, or got distracted by some supermodel or A-list actress that he met that night. It makes him unreliable and outright infuriating at times but people will put up with it because he's Tony Stark and face time with him is worth it's weight in gold.
Functioning Alcoholic
Tony is rather fond of the drink. Or rather, overfond. If he doesn't have something caffaine or energy drink based in his hand, you can bet it's going to be some exquisite and expensive libation of some sort. This doesn't mean he goes out heroing drunk on purpose, but it might mean he's been sauced stopping something before. But he's a very accomplished drunk and can cover it pretty well most of the time if he needs to. And many are the times he's been functioning dreadfully hungover.
Beautiful Mind
They say that Albert Einstein forgot to wear socks. Tony Stark has several personality quirks that come with being far to intelligent for any one man. For one, he's OCD and does not like anything to be out of place… which is not to say that he's neat, which he most certainly is not. Only that he understands the order in his chaos. He can tell you exactly where a hairpin is on his cluttered desk, but if someone moves a glass out of place he's liable to freak out. He also doesn't like to be handed anything other than by Pepper Potts. While this isn't as obvious to some, since he's known to be eccentric, it really and truly bothers him on a psychological level to be touched without his consent.
Self Opinion
Being told how good you are at things, being extremely good at things, and being very successful at things will bring about more than a few character flaws. Tony is egotistica, narcissistic, cocky, and arrogant. He thinks rather highly of himself, and what he's capable of - and rightly so. Is it bragging if you can back it up? Tony would so no, it's a mere statement of fact.
Loyal
Because Tony has so few friends and has pushed most people away, he naturally protects those who have cracked into his inner sanctum with ruthless, almost blind determination when they need him. They could bleed him dry without him ever thinking twice about it… they truly do have the keys to the palace and could, potentially, be used against him by nefarious individuals if they so deemed it to be a necessity.
Reputation
As carefully constructed a lie as his reputation might be, he is a victim of the success. People ''believe'' the hype. They think he is a womanizer, playboy, flamboyant, and often hedonist spoiled brat. Some of that ''is'' true, to an extent, but only because he's been playing the part so long it's just become his reality. When he switches off and returns home he's just a nerd in pajamas, but to the world he's ''TONY STARK'' and people flock to that kind of magnetic personality, much to his chagrin. There's also those who despise him for it and think he's squandering the wealth he was ''given''.
Hedonist
Tony is very much a "if it feels good, do it" kinda guy. It's what has led him down the slippery slope of being a playboy and to the many run ins with the media that he's left for Pepper to have to clean up in his wake. If he's taken by whimsy, and the urge, he's liable to do anything. Does he have self control and willpower? Of course he does, but how in the world are THOSE fun?
Weak Willpower
Tony's willpower is weakest when in certain situations and thus will be likelier to be the target of seduction ploys, or easily be distracted by women. He's also been known to show up slightly (or not so slightly) inebriated or at least well lubricated to both business and social functions. His inability to say no, say stop, or the rarity of hearing them usually feed directly into his hedonistic, womanizing ways.