Goku's shows are original DB and GT, the Z series is centered around Gohan's growing, maturing, and power, and Toriyama had stated he intended for Gohan to be the ultimate hero against Buu. Though his baka editor and majority of fans in Japan were pressuring him to bring Goku back. Think about it how the show's sagas progressed.Rocketman wrote:Z is Goku's show. Gohan is the special guest star.Conan the SSJ wrote: Regaurding Gohan, I personally love the idea that he's getting the most forms/characters, Z is his show IMO.
The Saiyan saga was basicly the birth of Gohan's training and hidden power peeks, he eventually proved he had the power to take down the likes of even Vegeta. The Namek/Frieza sagas gave us MANY peeks into his mysterious hidden powers while Goku was either in outer space or in the Rejuvination Chamber, and showed that even when Frieza was in his final form, Gohan still had the stamina and power to go one on one with him after all he went through. The Garlic Jr. saga alone, while pure filler, proved that Gohan could save Earth without Goku, and Toei gave us a treat of how much more his show Z was. Next came the Android arc, which the first 50% of it had Gohan as a mere side character and focused on Trunks, Vegeta, and Goku, it did show that Gohan ultimatly became the youngest Super Saiyan (until Goten and Present Trunks that is) and in the Cell Games, Goku gave full faith to him that he could beat Cell, which he did and became the hero of Earth. Finally came the Buu arc, which skipped straight to his high school years and an unfortunate drop of power (which he later regained in the first battle with fat Buu), as Gohan was taken out of action by Buu, Kaioshin saw the potential in Gohan of him being the one to "draw the Z sword and end the universe's supreme evil", Gohan hence fourth drew the Z sword, shattered it (freeing Old Kaioshin), and Old Kaioshin saw the same potential in Gohan his decendant did. With the end of Z approaching, Gohan had his highest possible hidden powers unlocked by Old Kaioshin, and thus became the strongest unfused "good" character in the show (next to Goku's 100% SSJ3), he was supposed to defeat Buu, however Toriyama's editor and nit-picky fans balled the poor guy with demands for Goku to be the hero, thus Buu absorbed Gohan and eventually killed him with Earth, however Gohan did get one last significant importance in Z: rather anyone likes it or not, he alone had to of given at least over half the energy for Goku's ultimate Genki-dama against Kid Buu.