Related to the earlier post, as a way to not have the whole Majin Buu saga feel tacked on, I would have the group of bear thieves that Son Goku faces in the Pilaf arc have the Majin mark on their forehead, Son Goku would defeat them, and after the Uranai Baba arc, the Dragon Ball Gang would all go back to Muten Roshi's house before going their separate ways, only to be interrupted by King Gurumes, who blows up Muten Roshi's house in an attempt to get revenge against Son Goku for defeating his underlings, I've got the rest of the plot written, but the gist of it is,
The DB Gang goes after Gurumes, who has discovered Majin Boo's whereabouts on Earth and is using a machine to suck out the Ki of the people of Earth to revive Majin Boo, planning to use him for himself and overthrow Babidi, while being completely ignorant of how powerful and uncontrollable Majin Boo really is, only hearing stories of him from his master, the DB Gang beats up Gurume's minions and Gurumes himself and also destroy the machine and hideout before Majin Boo can be revived and the people of Earth can be killed, but before dying in the explosion, Gurumes sends a distress signal to his master, but due to faulty equipment, the message goes out slower than usual, not reaching Babidi until Age 774, resulting in the events of the Majin Boo saga.