Here are more villains (villains that I made up) that should appear in the Dragon Ball franchise:
1. Major Buu: An incarnation of Majin Buu who is created when Good Buu eats multiple donuts (not knowing that they are dog food flavored) but spits them out due to hating how they taste. Major Buu's personality is much like that of Majora from The Legend Of Zelda. He looks exactly like Super Buu, except that he is the size of a giant. Major Buu's goal is to destory the galaxy.
2. Muscular Buu: Another incarnation of Majin Buu who is created when Good Buu eats a weight in a gym (thinking it is food) but spits it out due to disliking how it tastes. As his name suggests, he is extremely muscular. Muscular Buu's personality is much like that of Muscular from My Hero Academia. Muscular Buu's goal is to destroy the Earth.
3. Dark Mr. Satan: An evil version of Mr. Satan who was created by Frieza while he was in Hell. After Frieza created him while he was in Hell, he told Dark Mr. Satan to enter Earth. Afterwards, Dark Mr. Satan starting killing many people and destroying many galaxies. He has thick long black hair. Dark Mr. Satan's goal is to take over the universe and turn everyone in it that he didn't kill into mindless robotic versions of themselves that wouldn't be able to do anything without orders from him. He is the archenemy of Good Buu and the real Mr. Satan.
4. Vaato: An ancient spirit of evil who was sealed inside the skull of a dead person. Like Majora, he turned into multpile disturbing forms and tried to break his enemies physically and psychologically. His goal is to destroy all universes so that it will make him so powerful that he will become a god. He is another enemy of the Z-Fighters.