As one of the few "normies" on the Avengers, Hawkeye's a pretty remarkable cat. Not only is he a crack shot with his bow, but he's also one of the most committed members of the team. To him, being an Avenger is a really important job—and he's out to do that job to the best of his ability. We're talking zero sick days here, people.
As well as his lessons in professionalism, Hawkeye also has a lot to teach his teammates about family. For starters, he has one. That makes him odd in a world of swinging, single, incredibly-dysfunctional superheroes. At the end of the day, he's the one who gets to go home to his wife and kids, and it's clear that the other Avengers really envy him for that.
The existence of Hawkeye's family comes as quite a surprise to many of his teammates. When he brings his fellow Avengers back to meet to his wife Laura and their two kids at their sprawling house out in the country, only Black Widow seems to be in on the secret.
Surprise or not, the team's trip to the country couldn't have come at a better time. After getting zapped by Wanda Maximoff's mind melt, they are in need of some serious r n' r. This fact is readily apparent to Hawkeye's wife:
Laura Barton: You know I totally support your Avenging. I couldn't be prouder. But I see those guys, those gods…
Hawkeye: You don't think they need me.
Laura Barton: I think they do, which is a lot scarier. They're a mess.
Here Laura sees something in her husband that the other superheroes don't have. Though he's continually, almost comically, overlooked as a member of the team, Hawkeye's commitment to the job makes him a standout. In many ways, he's able really to treat it like regular employment: punching in, doing his best, then punching out again to be with his family. The other heroes don't seem to have that avenue of escape, which might explain why they take themselves so seriously all the time.
Seeing the Big Picture
We get a sense of Hawkeye's healthy outlook on things when he's helping the Avengers in their final battle on flying Sokovia. He's teamed up with the now-good Wanda Maximoff, who, in the midst of all the robotic carnage, starts to have a major freak-out about how everything is her fault. Hawkeye's the one to talk her out of it, though:
Hawkeye: The city is flying. We're fighting an army of robots, and I have a bow and arrow. None of this makes sense, but I'm going back out there because it's my job.
He's right on all counts here. It really doesn't make much sense when you take a step back and think about it. So his advice is really just not to think about it too much. Instead, he tells Wanda to do her job. He's a professional, and if she wants to help, she'll need to be one, too.
Hawkeye's clock-punching rhetoric doesn't mean that he takes his commitments any less seriously, though. When he jumps out of the airboat to rescue a little Sokovian boy who was left behind, he shows us that he's willing to put his life on the line to save every last civilian.
Luckily (for him, anyway), Pietro Maximoff is there to take the many…many bullets intended for Hawkeye and the boy. He falls down dead, and Hawkeye lives to go back to work another day. But before he does, though, he's got to go back to his family. There's a sunroom floor that needs replacing.