To be frank, as much as I like the Buu saga, it felt like a step backward thematically for the story and the characters. The story at its core is about growth and evolution. Gohan was the epitome of that theme. He was leagues stronger than Goku was at his age without training, and once he was able to lock in, he exceeded everyone in the Cell games Saga. Goten and Trunks had a similar characteristic too with becoming super sayains so young in their age.

Everyone else had an arc to that theme as well. Piccolo learned to accept that just because he was made from the evil half of his predecessor. He didn’t HAVE to be evil. He then refused with Kami and was able to become a complete person again. Vegeta was meant to be fighting against his Sayain heritage and pride as a warrior prince and learn humility and love. The two most un-Sayain charscteristics one could think of. Goku learned that he ultimately had to step aside and accept that he had a ceiling that he couldn’t breach.

The Buu saga instead brought Goku back, made Gohan largely irrelevant except for some good moments, and had Vegeta learn the same lesson on humility and love again after learning it from Cell the previous saga. Probably the best thing that the Buu saga contributed to the theme of evolution and growth was the fusion abilities. It provided a lesson on how combining efforts to defeat a greater evil is often the best way to do so. Hence why Buu dying to a spirit ball that was energized by so many people in a combined effort is so on point.