Always Save the Girl: Subverted. When the wooden stairs in the mineshaft begin to fall apart, Ben has the choice to save the Declaration of Independence or Abigail from falling to their doom. It seems he's chosen the Declaration over Abigail, but he actually Takes a Third Option.
Badass Bookworm: Ben is very well versed in history and historical facts in general. He also goes toe to toe with Ian and his thugs and dives from very high up into the Hudson.
Chekhov's Hobby: When the FBI rattle off Ben's history they mention he was in the Navy ROTC and a certified Navy Diver. Later when getting a change of clothes and looking up the clue to the Liberty Bell, Ben mentions his watch was a rather expensive diving watch. It is all suggested so quickly it doesn't come across as "In Your Face" but only adds validity to the moment when Ben escapes the FBI. Truth in Television, as a large number of treasure hunters are certified divers because a great deal of treasure hunting involves shipwrecks.
Couldn't Find a Pen: Due to the absence of ink, Ben stabs his thumb with a knife to make a substance to read the stem engravings on the pipe in the first film. Riley is noticeably squicked out.
Guile Hero: Ben uses his brains to solve problems, and rarely gets into a situation where he has to use his fists or a gun.
Hey, Catch!: In the first film with a lit flare in a room filled with gunpowder to escape being shot by Shaw.
Indy Ploy: While Ben usually plans things out, he's not above making it up as he goes if things go off the rails.
Will Not Tell a Lie: Ben is incredibly honest throughout 95% of both films, and the remaining 5% consists of fairly harmless subterfuge with an ultimate goal that leaves anyone that isn't himself out of the line of fire. Both Sadusky and the President call him a terrible negotiator as a result. He also reminds Ian that they played poker together and that he can't bluff.
Adorkable: He's a bit of an oddball, but he's just so enthusiastic about his eccentricities that you can't help but love him.
Ambiguously Jewish: Very slightly. During the infiltration of the National Archives, Riley wishes Ben a "Mazel tov" over radio, Yiddish for "Good luck".
Butt-Monkey: If someone's getting the short end of the stick in a plan, chances are it's gonna be Riley.
Undying Loyalty: Despite his seemingly cowardly nature compared to Ben, Riley has gone to great lengths for Ben's sake through both films. In the first film, he was willing to risk going to jail for a very long time to help Ben steal the Declaration, not to mention risking death by being shot by Ian's thugs just because Ben asked him to. In the second film, when Ben is about to stick his hand in a hole in an attempt to find the city of gold, Riley immediately offers to do it instead as soon as he hears that it could be a horrible trap.
The Watson: He's not as ridiculously well-versed in history as Ben and Abigail are, and is well aware of it. The one time he knows something that they don't, he takes a moment to savor the feeling.
This could also be an allusion to the fact that Justin Bartha is Jewish.
Patrick Henry Gates
Agent Scully: Patrick is the family skeptic; he believes the treasure is a myth and that Ben is wasting his life looking for it, unlike his father or Ben himself.
Distressed Dude: In the first film, he is captured by Ian at some point after Ben goes to Philadelphia to be used as leverage against Ben.
The Mole: An unwitting one in the second film when he is stunned by Mitch's men and they clone his phone, meaning that whatever Ben tells him, they know.
My Rule-Fu Is Stronger Than Yours: To sneak Ben onto Mount Vernon Patrick fishes in the Virginian waters. When approached by Secret Service on a boat, they tell him to leave. Patrick tells them that the state constitution gives him the right to fish in any public water area. The agent tells him he has the right to detain Patrick for 48 hours without cause. Patrick nervously chuckles and leaves.
Nice Job Breaking It, Hero!: In a Deleted Scene, Patrick accidentally caused the flooding in the caverns beneath Mount Rushmore when he opens a door and water starts flowing past him and Emily, leading to Cibola almost getting flooded and Mitch drowning.
Foreign Cuss Word: She drops a verdammt when arguing with Ben about the Declaration after escaping Ian after the Archives heist.
Immigrant Patriotism: She's originally from Germany, but she's still a proud American. (Although her Anglo name suggests her parents may have been Americans living abroad.)
FBI Agent: In charge of the Declaration theft investigation.
Sympathetic Inspector Antagonist: He's a genuinely good guy, but he's also a good FBI Agent. That is, he wants to retrieve the Declaration and catch a few criminals. He ultimately agrees to let Ben go at the end of the first film in exchange for the return of the Declaration and Ben leading him to Ian's crew.
Known Only by Their Nickname: It's easy to miss, but when Ben is chained up with the FBI (just before Ian calls them up), an agent can be heard saying, "Looks like Ian Howe is a false identity". Ian's true name never gets mentioned at any point in the film.
The Team Benefactor: Ian was Ben's main financier before they turned on each other. Ben mentions later in the film that Ian has "nearly unlimited resources."