Thankfully, Hank and Gomie’s entrance at this point in the series at least makes a lot of narrative sense. With Gus and Lalo’s crews looking to disrupt each other’s cash flows, it checks out that their shenanigans would cause them to register on the DEA’s radar. Lalo enlists Jimmy McGill to represent Krazy-8 and instruct him to deliver a very specific message to the police and become a criminal informant in hope of a reduced sentence. Instead of bringing in some faceless suits to receive that message, why not utilize two agents that a large portion of the audience already is familiar with? Also, it gives the actors a chance to reunite with a lot of the crew they worked alongside for a long time.
Speaking of Dean Norris’ return to the Breaking Bad universe, star Bob Odenkirk said “For me the show didn’t end. Breaking Bad stopped and then we started Better Call Saul. It was in the same place with the same crew but with different sets and different aspects to the character. I think Dean had a more interesting experience, having left the show and in his mind and his heart feeling like, ‘Well, that’s over,’ then being surprised to find himself back there. A lot of the same crew still, even five years in – 40% of our crew was Breaking Bad people. That’s a lot of people to carry this far into the future. Dean was the one who had a remarkable experience and I was happy to see him again.”
Hank and Gomie will presumably mostly remain as lawmen on the periphery, instead of frequent POV characters, and that’s how they likely should be used. Hank was given as full of a character arc as anyone on Breaking Bad, and thus there isn’t mainly places you can go with the guy in a prequel. Whereas Gus and Mike were a bit enigmatic in Breaking Bad, Hank was an open book. He was a cocky, boisterous agent whose insensitivity masked an insecure side. Hank then was humbled by violence, forcing him to rebuild his confidence and rethink his macho posturing. The Hank we find in Better Call Saul is the jokey man’s man from the early days of Breaking Bad, not the reclusive, contemplative mineral man he became. All of the character development happened on the other show, therefore we’re unlikely to learn anything new that changes our understanding of Hank.
Maybe this could be considered more fan service, but an onscreen authority figure is a great, logical added foil for not only the Gus and Lalo storyline, but for Jimmy to outsmart during his race to the bottom. This isn’t like Walt or Jesse appearing just for the hell of it, this is the show reminding us that there are legal repercussions for everyone involved in the cartel storyline, which now includes our lead character. Why not make the face of those consequences a familiar one?