My family enjoys this action show. Here's a break down of it as based on last year's episodes & this year's opener.
This show is a bit reminiscent of the A-Team without the gunfights and explosions. In fact, most times that I remember explosions or gun fire, the "bad" guys were doing it. Even the Leverage team's muscle guy stated in an early episode that he doesn't like guns; he does, however, engage in hand to hand fighting.
The show has a quick, light humor and crazy plans which the team pulls off. Not all the plans turn out as expected.
About half of the team are wanted by the police; Nate, their leader, & Sophie, a con artist turned actress, are not. Nate, in the early episodes, turns the group onto using their skills to help people who can't be helped by the police or FBI. As they admit in this season's opener, they have all gotten hooked on being "good guys" and they don't want to go back to their previous lives of crime.
Now their skills do involve computer hacking, breaking and entering, conning people, etc. and they do point out that if they got caught, they'd get arrested. But they also make a big point wanting to help people in trouble. They also care about each other as their relationships grow.
Nate is battling alcoholism (triggered by his son's death) and 2 characters flirt some. Nate & Sophie also had a past romantic connection, but it's relayed through conservations & looks.
Leverage is really not much more violent than some of the Saturday morning cartoons, so I think some 10 year olds could handle it. However, since it isn't animated and some situations step away from reality, my husband & I do watch and talk about it with our kids. It's also the kind of show that could lend itself to an "edgier" content, so you need to keep an eye out for that.