There could be a new alien race that comes to Earth. They might be peaceful at first but then something causes a conflict.
Maybe a new Saiyan with a special ability, like the power to control time or space in a different way than Whis. This new Saiyan could be from a lost colony of Saiyans that was thought to be destroyed. They could bring new knowledge and skills to the existing Saiyan community, and also introduce new power - up techniques. They might also have a different culture compared to the Saiyans we already know, which could lead to some interesting interactions and storylines.
Maybe some new Saiyans from another part of the universe.
Perhaps it will focus on the next generation of Saiyans. They might discover new forms or techniques that are unique to them. It could also involve a new kind of Dragon Ball quest, where the characters have to find the balls in a completely different dimension or under some strange circumstances. For example, there could be a time limit set by an unknown force, and if they don't gather the balls in time, something catastrophic will happen to the entire universe.
I'm not sure exactly who the important characters are without playing the story fully. But it could be the new characters themselves that are important as they are likely to drive the plot forward.
Hit is also a great new character. His time - skipping ability was a unique power in the Dragon Ball universe. He was an assassin with his own code of honor, which made his character complex and engaging. He had some great battles against Goku, and his fighting style was different from what we had seen before in the series.
Definitely Goten and Trunks. They have a lot of room for development in fanfiction. Since they are the sons of two of the most powerful Saiyans, fans like to imagine them achieving even greater power levels. Also, Uub is quite popular. He has the potential to be a very strong character as he is the reincarnation of Majin Buu. Fans are interested in seeing how he fits into the new generation of Dragon Ball stories.
Goku and Vegeta are very likely to be protagonists. They are the main characters in most of the Dragon Ball stories.
A character with the ability to transform into different elements like fire, water, or earth. This would add a new dynamic to the battles. Another could be a small, alien creature that has the power to control the minds of others, creating chaos among the heroes. There could also be a warrior from a lost civilization in the Macho Universe who has a unique fighting style that combines swordsmanship and Ki blasts.
There are original characters that are powerful hybrids. For example, a character who is part Saiyan, part Namekian. They would have the strength of a Saiyan and the regeneration ability of a Namekian. This kind of character can bring a fresh dynamic to the story and is often well - liked in fanfiction. They can befriend the main characters and help them in battles in new and interesting ways.
A talking bird could be a new character. It could be Rapunzel's friend in the tower, helping her pass the time and giving her advice on how to escape. Another new character could be a witch's apprentice who feels sorry for Rapunzel and tries to help her.
There might be a tech - savvy inventor. This character could help Cinderella create some amazing gadgets to attend the ball without relying on magic, like a self - flying carriage.