Breaking Bad and Better Call Saul are basically extensions of each other as a series. Breaking Bad, of course, aired and ended first, with the death of Walter White (Bryan Cranston) and Jesse getting away from the Nazi compound and evading the police. We find out in the El Camino movie that Jesse managed to get out of Albuquerque with the help of the vacuum cleaner guy and start a new life in Alaska. Better Call Saul, which was spun off from Breaking Bad, is partly an origin story for the character of Saul Goodman, showing his life before the Breaking Bad timeline as a two-bit slip-and-fall crook turned lawyer named Jimmy McGill who let greed and revenge rule his life (which is where most of the series spent its time) and partly a sequel to Breaking Bad, showing that Saul ended up managing a Cinnabon in Omaha Nebraska under the name "Gene". Gene could not leave Saul totally behind, and as shown in the second half of the final season, he got greedy and ended up getting caught.
Between the two shows, none of the main characters had what you call a happily ever after. The closest (at least as we know so far) was Jesse, which to me is actually the best outcome since he was the least "bad" of the worst people in Breaking Bad, never turned into the monster that Walter did, and was ready to let go of that life but was constantly pulled back in by Walter's manipulation. Of course, Walter ended up dying, and as we find definitively out in BCS, Skylar made a deal to avoid prison, and Gus and Mike were dead by the end of Breaking Bad so even if the authorities found out about their roles, they were not around to be punished either. So, ultimately, that left Saul/Jimmy to face the consequences of what happened during Breaking Bad.
Jimmy was kind of a sad-sack character, at least initially in BCS, who had genuinely tried to move on from his small-time crime life to become a lawyer and follow in his brother's footsteps. Ironically, had his brother not torpedoed him, Jimmy probably would not have made the transition to Saul. But, that betrayal wounded him so much he would always give in to greed and would always get revenge on his perceived enemies, which inadvertently led to the deaths of his brother Chuck and to Howard Hamlin. And, his greed led to him running scams in Omaha instead of getting out when he could have and then taking risks that ended up with him getting arrested in a dumpster.
Ultimately, Saul was never as evil as Gus or Walter, but he was responsible for Walter becoming as successful as he did and thus had culpability for the things Walter did. For the first time in a long time Saul, having negotiated himself a seven-year prison sentence when he was offered 30 years and facing life plus 180 years if he went to trial, did something against his own interests when he admitted to everything to save Kim, the only person he cared about as much as he cared about himself. So, Jesse ending up in Alaska living free and Saul in prison for 86 years seems to be where the last surviving characters from Breaking Bad should have ended up. Personally, I do not think there is any reason to revisit the Breaking Bad universe and I hope Vice Gilligan and Peter Gould leave it alone. I am not sure that a Kim-centric show is needed, or would be as good as either BB or BCS. I am fine with it just being where it is with everyone living the rest of their lives. If they did want to revive the universe again, a movie in the vein of El Camino with Jesse being caught and extradited to New Mexico with Kim representing him would be a good way to do it. But, I do not think another series is needed and I doubt that they could catch lightning in a bottle a third time and make a series as good as either BB or BCS.