Breaking Bad make a lot of sense, though, as the show has a theme of "transformation," just like its predecessor.
In fact, one could say the transformation of Jimmy McGill is, in many ways, more dramatic than Walter White's. Plenty of elements from the first season are completely upended by the end of it. These characters or ideas are just unrecognizable in the season finale compared to the beginning.
Bill Oakley
Bill Oakley was one of first lawyer rivals that audiences were introduced to in the show. His first scene, where he endlessly shut down Jimmy's requests for a plea bargain, is hilarious. He doesn't really have a lot of screen time after that, though. In fact, audiences wouldn't even learn his name for a few seasons.
But his role in the finale is massive, as he plays the role of Saul Goodman's co-counsel. Circles are run around him by the much more experienced lawyer, Saul, in contrast to their first encounter. He's a character that fans wouldn't have expected to see in the finale, but it was great at illustrating how far things have come.
The Protagonist's Name
One thing notable about the protagonist of Better Call Saul is his many personas. He takes a lot of names throughout the series, which makes it shocking to that his original name was a focal point of early season one. When audiences meet Jimmy McGill, he is literally fighting to be able to practice law under his own name.
Jimmy is being attacked by Hamlin, Hamlin, and McGill when the series opens. They are doing their best to stop him from using the McGill name, even if it's his own name. By the end of the show, Jimmy isn't using his own name by choice anymore. While he does ask to be called James McGill in the finale, it's a desperate plea rather than a defiant request.
The Kettlemans
The Ketlleman family are the first real antagonists introduced in Better Call Saul. While Tuco Salamanca is a more deadly threat to Jimmy, he gets wrapped up in Greg and Betsy's schemes for more time. His attempts to help them end up embroiling him in criminal plots. He even thinks of them when he decides to stop following in his brother's footsteps.
In contrast, the Kettlemans in the finale season are typical patsies. Saul and Kim manipulate them in their schemes to get back at Howard. He perfectly manipulates these two characters who gave him so much trouble, which shows how far he and Kim have come.
Nacho's Importance
Michael Mando's acting prowess sold Ignacio "Nacho" Varga as one of its best characters, and his transition from criminal to forced traitor is heartbreaking. He effectively serves as the show's third protagonist, especially in later seasons. This makes returning to season one kind of shocking.
Nacho appears in only around four episodes of the first season and he isn't even introduced until episode two as basically a background character. It isn't until his second season episodes with Mike that he finally gets prominence. It does help amplify his status as a small-time crook thrust into a big world, though.
Jimmy & Kim's Relationship
Jimmy and Kim's relationship in Better Call Saul is definitely the heart of the show. It's not immediately apparent in the earliest season, though. Most of season one has Jimmy caring for his brother Chuck instead of Kim. Only a few episodes in do audiences learn their background relationship is actually quite substantial.
Season 6's plot is inextricably linked to Kim and Jimmy's relationship, even in the episodes where Kim doesn't appear. It's revealed that Kim played a pivotal role in pushing Jimmy to become Saul Goodman. This makes her absence in most of the first episodes (and in Breaking Bad) extremely striking.
The Setting & Time
The first scene of Better Call Saul is a flash-forward to events after Breaking Bad. It's a pretty striking scene, as it shows Saul Goodman as the nervous and reserved Gene. But the rest of the season basically has nothing to do with that scene. It also takes place in a frigid small town, which is a big contrast to the hot desert city the main show takes place in.
A lot of the final season takes place in this time frame and setting, unlike the first season. It's also very unlike the first time audiences see Gene as well. At the end of the show, he's downright nasty and mean-spirited. The past and the future are often different, but it goes especially far in this show.
The ing Cast
As mentioned, the bulk of Better Call Saul's final season takes place in the future. In fact, it takes place after Breaking Bad and its sequel, El Camino. Given that it was a prequel, most of the cast of Saul also appeared in Breaking Bad. By this point, most of them are dead.
Jimmy's brother and his law partner, Mike, Tuco, Gus, and the cartels are all gone by this point. This is despite the fact that they were major players in the first season, even if they didn't appear. Mike's absence is especially notable, given that he was essentially the show's second protagonist in the early seasons.
Jimmy's Lawyer Skills
When we meet Jimmy McGill, he is an excellent debater. He's charismatic and is a good manipulator from then up until the end of the series. His skill as a lawyer, however, is much poorer, as he's constantly losing cases. Throughout the first season, the audience sees him learn to adapt to the straight and narrow, but it's still tough for him.
By the series' end, he is a perfectly slimy and capable attorney. He talks himself down from a life sentence to one of merely a few years. He does this by mixing his charisma with the law, which is totally different from the path he was on when audiences ed him.
Chuck McGill
There are no villains as well-rounded on BCS as Chuck McGill, even by the series' end. While Lalo Salamanca was a heinous and active threat and Jimmy himself would prove to be a monster in the last few episodes, audiences couldn't help to love to hate Chuck even after he'd been dead for a few seasons. But ing Chuck in the first season is like night and day.
Chuck plays the role of the cautious but needy and kind relative so well. While it's clear he holds some dislike for Jimmy, it's nothing like the specter that haunts Jimmy's life in the modern day. Jimmy would imply his relationship with Chuck was his biggest regret, but it would be hard to see why after just watching the first few episodes of season one.
Howard Hamlin
Howard Hamlin is the textbook stuck-up rich guy rival who has no tact or awareness of the world around him. He's a pretentious jerk who constantly obstructs people around him on a whim and has no redeeming qualities; he's simply an obstacle for Saul Goodman to knock down in his quest to rise up. At least, this is what audiences thought during season one, and also what Kim and Jimmy thought throughout the show.
Holding this attitude towards Howard ultimately causes the duo to perform some truly heinous acts against him. They and the audience are able to laugh it off because "he deserves it." By the end of the show, viewers realize that he's just a normal guy like anyone else, and he gets killed because of Kim and Jimmy's views. He tried his best to improve as a person, and viewers see that, but he still ultimately gets struck down unfairly anyway. The perception of Howard changed drastically from seasons one to six, just like the protagonist himself.