With three more Fast & Furious movies set to debut before the end of The Fast Saga, the franchise might have plans to bring back Brian O'Conner, but they shouldn't. Paul Walker portrayed the character since the film series launched with 2001's The Fast and the Furious. After starring alongside Vin Diesel in the first installment, Walker returned for the first sequel, 2 Fast 2 Furious. The actor then appeared in four additional sequels before his untimely death in 2013. Due to the tragic event, the character of Brian was retired from the Fast & Furious franchise following Furious 7, and it would be best if the series carried on with that decision.
When Brian first appeared in The Fast and the Furious, he was an undercover cop who purposely infiltrated the Los Angeles street racing scene for a special mission. During his investigation, he fell in with Dominic Toretto (Diesel) and a group of criminals. In time, Brian left his career in law enforcement behind, aligning with Dom in his globetrotting heists. The two became more like brothers as they got older, which was fitting since Brian started a family with Dom's sister, Mia (Jordan Brewster).
When Walker passed away before filming ended on Furious 7, director James Wan retooled Brian's arc. While the original actor provided a lot of useful footage, Walker's brothers, Caleb and Cody, stepped in to help polish off Brian's presence with a mix of necessary CGI. After Deckard Shaw (Jason Statham) was captured and terrorist Mose Jakande (Djimon Hounsou) was killed, Dom, Brian, and the crew were free to live peaceful lives. On a tropical beach, the group watched on as a newly retired Brian played with his young son. He then jumped behind the wheel of his car to face off with Dom one more time before driving in different directions. The moment served as the perfect sendoff for Walker and his long-running character. Bringing him back in a large capacity could possibly do more harm than good.
With an end to the original Fast & Furious film series now in sight, Universal Studios might be tempted to bring Brian back to fully hone in on the concept of an endgame. It's no question that Brian remains a core figure to the franchise, even with his absense. That said, a return from the character would diminish his original sendoff. With Mia's planned presence in F9, there's already discussions regarding Brian's whereabouts. The same questions will probably arise in the final two Fast & Furious installments.
While the Walker family have shared their approval in allowing their brother's likeness be used for future installments, it would be a controversial aspect if the studio went that route. Rather than feature Brian through questionable means, it would be best to carry on his legacy through other ways. It's more meaningful to keep the character retired and happily focused on his growing family. That said, the series could elect to present Walker's time in the Fast & Furious franchise through flashbacks or unused archival footage in a respectful, yet limited capacity. Even if it's a tribute in the final film's end credits, one last goodbye to the original cast wouldn't be a bad idea.