When Leverage begins, Eliot is termed a "retrieval specialist," but the team affectionately refers to him as their hitter. He takes care of the more physical aspects of their job, throwing punches when the rest of the team can't. His status as the team's muscle means that a lot of their enemies tend to underestimate him, and so do the fans at first.
There's a lot more to Eliot than his tendency to punch his way out of situations. As the show continued on for its five seasons, his character received more backstory and more depth, allowing the audience to get to know him better. That trend will likely continue when Eliot returns in the series revival.
Best: He's Incredibly Observant
One of the running jokes of the series is that Eliot can identify something by a seemingly innocuous detail. He knows what agency a helicopter is from by the sound their blades make, what model of a gun is fired just from hearing the gunshot, and whether or not someone is a government agent based on their shoes.
While it's always funny to see Eliot identify something the rest of the team can't, it also reveals just how observant he is and how good his memory is. It's one of the many ways people underestimate him.
Worst: Eliot Has Little Patience
Eliot is used to being a person of action. It doesn't sit well with him when he has to wait on the rest of the team before he can get something done.
This is especially true of his interactions with Hardison. Hardison is often the person on the other end of the ear piece that Eliot has to depend on to open doors or give him an exit when he's exposed. Eliot doesn't have the patience for the amount of time it might take Hardison to do that part of the job. He also tends to get very short with Hardison and Parker if they make jokes during the con, intent on getting in and getting the job done as quickly as possible.
Best: He's Selfless
Eliot might grumble about his role on the team quite a bit, and he might get short with Hardison and Parker a lot, but he's always willing to put himself in the line of fire for them. It is, quite literally, his job to get between the rest of his teammates and a bullet.
Eliot takes that job very seriously. He's willing to take a hit to protect a client, a bullet for his teammates, and never once thinks twice about the possibility that he could die in their place. He does it, over and over again, without anyone even having to ask him to.
Worst: Eliot Is Easily Distracted By Beautiful Women
This particular trait is definitely true for Eliot in the earlier seasons of the show more so than the later seasons. He tends to get close to female clients - or pretty women he meets over the course of the job.
When he does, he also tends to miss important moments. When he and the team are trying to help aspiring country music artist Katelyn get her music back from a corrupt record producer, for example, he removes his ear piece to spend some quality time with her. When he does, he misses out on Nate being held and attacked.
Best: He's Protective
Eliot doesn't just put himself into harm's way for people. He also actively tries to protect them - sometimes without even knowing him.
After pulling his first job with Hardison, and being openly hostile toward him, he still pulls him off his feet to get out of an exploding building. Eliot also meets a potential client when a pair of men in suits are pursuing her, and promptly knocks them out so he and Hardison can get the woman to safety. Even when Parker isn't physically in danger, but emotionally manipulated by a con man acting as a psychic, Eliot offers to kill the man on her behalf. He doesn't hesitate to protect the people who can't protect themselves.
Worst: He's Judgmental
All of the members of the Leverage team have done bad things in their lives, sometimes beyond just breaking the law. Though Eliot is well aware of this fact, he still judges his fellow thieves pretty harshly.
He makes fun of Hardison's interests, constantly talks about something being wrong with Parker despite knowing that she had a very different upbringing than most kids, and calls Sophie out for running games on the team despite knowing that she's a grifter. Eliot has no problem calling his teammates out for the things he judges them on, and it can sometimes cause friction between them.
Best: Eliot Stays True To Himself
When working with grifters and thieves, it's easy to fall into the trap of always playing a part. That's exactly what happens to Sophie, prompting her to take some time off from the group to put some of her old aliases to bed.
Eliot never doubts who he is, what he believes in, or what he wants. He knows himself well, and he doesn't sacrifice who he is to maintain his job. That's impressive considering how many different identities the team burns through and how many cities they have to leave behind.
Worst: He's Anti Male Affection
There's a running theme through the series of Eliot having no problem being there for Parker and Sophie, but balking any time Hardison shows him a little affection. Whenever Hardison attempts to go in for a hug, Eliot pushes him away - unless one of them almost dies.
It's an odd choice for the show considering how close the two are. Eliot is rarely open to a hug or a pat on the back from Hardison until the final episodes of the series. Considering Eliot challenges traditional ideas of masculinity in television with his skills in the kitchen and on a stage, having him be unwilling to show affection to his closest male friend doesn't really make sense. This could always be something rectified in the revival with years between the original series and the new storylines though.
Best: Eliot Is A Fast Learner
Eliot understands and picks up new skills just as fast as they're thrown at him. He understands the basics of Sophie's linguistic programming when she explains it once - so much so that he realizes she's programming him.
Eliot learns how to play baseball, sing a country song, be an enforcer for a hockey team, and even picks up quite a few of both Hardison and Parker's tricks in hacking and stealing, respectively. Any skill the team needs him to master, he does.
Worst: Violence Is His Response To Stress
One of the reasons so many enemies underestimate Eliot is because he does tend to hit first and ask questions later. While his tendency to punch things saves the lives of his friends, it also speaks to deeper issues.
When Eliot gets impatient, he wants to hit things. If an enemy gets the better of the team, he wants to hit a lot of things. When someone Eliot doesn't like enters their local hang out, like Sterling, he immediately resorts to hitting him. For Eliot, violence is a way to relieve his stress.