7. Han Solo
Boba Fett was introduced into Star Wars as the bounty hunter in pursuit of Han Solo due to unpaid debts to Jabba the Hutt. It was Boba Fett who delivered Han frozen in carbonite to Jabba, which is where Luke Skywalker, having advanced in his skills as a Jedi, came to rescue Han at the beginning of Return of the Jedi.
As a bounty hunter, Fett was just doing his job in capturing Han, but the job resulted in him nearly being eaten alive by the Sarlacc on Tatooine and the loss of his legendary Mandalorian armor. How would Boba Fett feel years later if he encountered Han, who had caused him so much difficulty, again? Since The Book of Boba Fett takes places within a few years after Return of the Jedi as the New Republic presses to gain more control over the galaxy once oppressed by the Empire, an encounter with Boba Fett would be a great way to show Han’s place within the New Republic and how he has influenced the state of the galaxy at the time.
With Boba Fett taking over Jabba’s criminal empire, if Han were to return to his former life of smuggling, Boba Fett could be a likely employer.