Britney Spears has just extended her pretty well-received Las Vegas residency — a stage show called Piece of Me, named after her 2007 hit of the same name — for another two years. That's both good (Britney stans rejoice!) and bad (two more years without a cross-country or world tour!) news, but promisingly, the pop star told E! News that in order to keep the show fresh during its new leg, she'd change things up considerably. "I definitely have some major changes planned," she told the network. "I'm getting together with my team this week to go over the set list, design some new costumes and dream up new props. There are a few songs that are fan favorites that I really want to add to the show." That last bit's the ticket: Piece of Me is getting a revamped set list, something that happened in miniature this year when she mixed in her Iggy Azalea collaboration "Pretty Girls," but beyond that, the show's remained largely the same since its 2013 debut. It includes massive hits, to be sure — including "...Baby One More Time," "Gimme More," and "Toxic" — but there are plenty of Britney deep cuts, not to mention hits, that haven't found their way to the Vegas stage just yet. With that in mind, SPIN picked five tracks that Britney can't forget to include this time around. "Trip to Your Heart," Femme Fatale Though this 2011 album was packed with successful singles like "Hold It Against Me" and "Till the World Ends" (though only the latter appears in the show's current set), "Trip to Your Heart" stands out as the project's most overlooked diamond in the rough. It's the sort of just-breathy enough sparkler that could get an audience going, with its dipping choruses and whispering verses. "Tom's Diner," Giorgio Moroder feat. Britney Spears, Déjà Vu https://www.youtube.com/embed/k0dLuNNNk5A While technically not a solo song, this 2015 glitchy cover of Suzanne Vega's weary, world-worn gem would mesh nicely with the rest of the set. Its lyrics speak pretty spectacularly to where Britney's head has been for the past few years, and it's vocoded enough that nobody would even mind that she's lip-synching the entire thing. Imagine a full-scale set of an actual diner, Britney sitting at the counter in a top hat and trench-coat, sipping her venti Starbucks iced latte. Brilliant. "Lace and Leather," Circus Spears performed this steamy Cirus cut nightly on her Femme Fatale tour, bringing men onstage and tying them up in chairs as she tempted and teased them. The song's a gorgeous, guitar-heavy Dr. Luke and Benny Blanco collaboration that'd be a bit less obvious than the current Piece of Me "I can be bad too" set piece, "Freakshow," during which celebrities in attendance are leashed and "forced" to walk around the stage on all fours. Nothing against that Blackout track, but "Lace and Leather" is the superior choice. Swapping it in would bring new life to a dated concept. "Passenger," Britney Jean Produced by Diplo and co-written by Katy Perry and Sia, "Passenger" was as widely ignored as the album on which it appeared. It opens with a sitar spiraling dangerously into a synthesized pattern of blips before Brit herself hops in with impassioned lyrics about taking her life one day at a time. Though a pretty jewel of a song, the star's all but ignored Britney Jean since its 2013 release, barring the show's opening "Work Bitch" performance and a late-act "Perfume." Though she added "Alien" to the mix for a short while, "Passenger" seems like the perfect way to acknowledge the album's existence beyond its singles. "I'm Not a Girl, Not Yet a Woman," Britney https://www.youtube.com/embed/IlV7RhT6zHs How — how — is one of the pop princess' most iconic hits not in the mix? It wasn't even there in the show's opening months, so perhaps Britney's simply outgrown the song's (obviously) dated message, but that's not necessarily stopped other stars before. Even if "Not a Girl" were simply folded into a medley or a preexisting Piece of Me track such as "Lucky," its appearance would put longtime fans over the edge.