Tony is fond of the Avengers.
(Why does that feel so lame to say? He's going to make jackets for them all, just to complete the absolutely dorkiness of it all. The Avengers. Jesus.)
He respects Natasha, because you can't see that woman in action(and in the kind of action she's usually in) and not respect her. Also he's a little afraid of her, so he usually tries to do whatever she says. 'Stark, hand me that gun holster.' 'Yes, Natasha.' 'Stark, call me Romanov. Or Widow.' 'Yes, Romanov.' 'Stark, eyes to yourself.' 'Yes, Romanov.'
He can think of only a couple people who he wouldn't worry about in a fight-Natasha is one of them. That girl could probably take a bullet to the face and take out a dozen men when she spits it back out. He respects Natasha, admires her skills, her beauty, her deadly accuracy... But there's something about her that he doesn't quite trust. Too many secrets, her gaze too guarded. She trusts them with her life, but that's about it..
And Tony gets a feeling that to her, that isn't a lot.
He likes Thor. Dude is funny as hell. Well, was. He hasn't seen much of him since he took his homicidal little brother back home to get a spanking or grounding or something or whatever gods do when one of their own goes rogue and tries to enslave another realm/kill everyone. The man(demigod?) did give him a hell of a beatdown, and Tony can appreciate a good ass kicking, even if it's his own. The man(demigod?) knows about honor and justice and what the right thing to do is, and Tony can appreciate that, too, since he's only ever had this vague idea of what the right thing to do is but it's sort of marred by 'what is the right thing to do for me?'.
No, Thor is a superhero. He's that stereotypical good guy who saves the damsel in distress, who saves the day, who has that stupid perfect hair and chiseled jaw and always somehow manages to look manly no matter what he does. He bets the guy could cosplay Rocky Horror Picture Show and still somehow make Tony look like a giant homo.
Hawkeye could draw a smiley face on his spine with his arrows. Tony doesn't know a lot about the guy, it's not as if they've really sat down and had a heart to heart, but he thinks if maybe the man comes to one or five of his parties and actually cuts loose he could learn to like the man. He has sharp eyes and steady hands, and Tony appreciates both.
Rogers just pisses him off. He will never admit to sort of liking the man, because he's too goody goody and old fashioned and everything about him just pisses him off. He'd especially never admit to having a list of all the people he'd prefer to have at his back in a fight, and that Rogers was on that list. Because that would be silly. And definitely not true.
He will not think about Nick Fury unless he has to. That man creeps him out. He thinks the eyepatch is just for show, but he hasn't ever asked and chances are, as long as Fury stays incredibly creepy, he won't. He can be smart outside of the lab, too, sometimes.
Tony tries not to think about Coulson at all.
While all the Avengers are unique and strong in their own ways and special little snowflakes respectively, and yeah, Tony would put his life on the line for them and what they believe in(what do they believe in? Do they have a motto? A catchphrase? Something?), has done so on more than one occasion, sort of, the one he would not hesitate to call a friend-whether he knows or consents to this or not-would be Banner.
The thing is, Tony Stark is a smart man. Well, that's kind of an understatement; Tony Stark is a fucking genius. He can finish a chess game with any given opponent in seven moves or less, he can rebuild an entire engine from scratch, he built a super fucking suit that can shoot missiles the size of a dog turd that could decimate a small town, he thinks he sort of deserves the title of 'genius'.
There's not many people who could keep up with him when he starts talking about ideas and technology and science, and not even half of them could stay interesting while they do it. And then he meets Doctor Banner, and Tony thinks he's a little bit in love.
Well, entirely in love with Pepper, who's so bossy and won't put up with any of his bullshit and really he thought his social security number was five what would he do without that sexy redhead? But Pepper doesn't speak the language he slips into when he goes down into the basement, understands the basics and maybe even a little bit more than that but she can't keep up a full on conversation about reactors and radiation and literally everything in between while trying to keep a straight face when playing poker.
Pepper is his girl, Rhodey is his bestfriend, but Bruce? Bruce is like that crazy halfbrother he never knew about who's actually like an evil twin in some ways except Tony is obviously prettier.
Tony might respect the rest of the Avengers, admire them, but Banner is the only one he looks up to. He snubs Fury, laughs at Thor, sneers at Rogers, but when Banner talks, Tony listens.
Right next to building a fully functioning supersuit made of awesome, he thinks the Hulk is one of the greatest things ever. He wasn't kidding when he told the doctor he was a big fan, and he honestly doesn't understand why everybody else isn't, either.
Sure, there's a chance he could lose control; but that's a risk with everyone. Nobody seemed overly concerned when he admitted he was Ironman. Everyone welcomed Clint back with open arms(even though that was sort of not his fault and if he ever says that out loud Natasha will have him down on the floor crying like a small child in 3.4 seconds flat); hell, even the giant mammoth who shot lightening with his giant hammer got a welcoming. But the brilliant mind who couldn't help it if he was different, who had tried to kill himself because of it was seen as a freak?
Tony Stark has only ever known white hot rage twice before. When he found out his company was supplying terrorists, and when the bastard who had been doing the supplying threatened Pepper. He's found that if he thinks about it, or if he stumbles across an offhand whispered conversation between some S.H.I.E.L.D. agents, that same rage threatens to make his vision tunnel.
There's not many people he would consider an intricate part of his household, a body that he would miss should they go missing(he will not say the f-word god damn it), but he considers Banner a part of that.
And if you mess with one of his, you mess with him. Rhodey might be in the military, Pepper might give Natasha a run for her money for being the scariest thing on heels, and Bruce might turn into a giant rage monster at the drop of a hat, but he's Ironman.
More than that, he's Tony fucking Stark.
And you don't piss him off.
Here's what I heard when Stark met Banner in the movie;
Tony: LET'S BE BFF ALWAYS
Bruce: But I could kill you all and I wouldn't even be able to control myself-
Bruce: You're not getting the severity of the situation-
Bruce: Mr. Stark you have to-