His movie should totally just be him against a
Carnival of Killers. He gets shot down on a remote planet, word gets out that there's a huge bounty on his head, and a horde of assassins, bounty hunters, and psychos descend upon the planet to end him.
And then he shows them all why he's the best in the business.
But since it's a Disney flick, give him a kid sidekick to show that he still has somewhat of a conscience, and he rescues him at the last moment (cause Boba Fett always wins). After he's finished off the remaining psychos, he leaves the kid behind with a souvenir, inspiring the kid to become a bounty hunter like him as he takes off with a stolen ship to hunt more bounties among the stars.