One possible analysis could be that it often explores the dynamic between two powerful and complex characters. Goku Black, with his menacing and somewhat twisted nature, and Vegeta, the proud Saiyan prince. In fanfics, their interactions can range from intense battles to unexpected alliances. Maybe it delves into how Vegeta would react to Goku Black's presence, given their different ideologies and power levels.
Then, introduce some shared experiences. Maybe they get trapped in a strange dimension together. In this new and dangerous place, they have to rely on each other's strengths. Goku's physical power and Frieza's cunning could be the keys to their survival. As they go through these experiences, they start to see each other in a new light and their relationship begins to change.
Many fanfics have a plot where Goku Black challenges Vegeta's place as the second - strongest Saiyan. This leads to a series of battles and power - up moments for both characters. There could also be a plot where Goku Black infiltrates Vegeta's family life, causing chaos and forcing Vegeta to not only protect his family but also prove his worth as a fighter. And sometimes, the plot focuses on the power struggle within the Saiyan race, with Goku Black representing a new and dangerous element to Vegeta's understanding of Saiyan power.
Well, it's not really a fair comparison. Goku and Vegeta are from a universe where superpowers are the norm. They can destroy planets even. The toughest character in Pulp Fiction might be good with a gun or in a street fight, but against Goku's Kamehameha or Vegeta's Galick Gun, they wouldn't stand a chance. Goku and Vegeta are on a whole different level of power compared to the characters in Pulp Fiction.
There could be a storyline where Beerus, out of boredom, decides to train Goku Black instead of fighting him. But Goku Black misinterprets this as a sign of weakness and attacks Beerus. This could lead to a battle where Beerus has to hold back at first to avoid killing Goku Black, but as the fight progresses, he realizes he has to use his full power to subdue him.
Well, if they were brothers in a fanfic, it could change how they interact with the other characters. Maybe they'd have a deeper understanding and fewer power struggles between them. Also, their family background and upbringing could be explored in new and interesting ways.
It's a bit hard to say for sure. Both Vegeta and Goku have their moments of strength. Goku has some unique powers and techniques that give him an edge at times, but Vegeta is no slouch either and constantly works to catch up and surpass Goku.