With Book of Boba Fett coming on December, I will give my thoughts and how i envision the show. First, i will mention some of the characters who will play a role and later on the plot.
1)Bounty Hunters: Apart of Boba and Fennec, there will be a lot of bounty hunters either helping and teaming up with Boba or, in the worst case, being antagonists of Fett. Here are some names of those bounty hunters to discuss:
A) Bossk and Dengar: Both of them had history with Boba, which started during the Clone Wars. I am sure that the gang will be reunited and they will become the first allies in the cause against the big baddie. IG-88 can appear as well but it depends if they use a different variant of the character (like the comics). He will probably be an antagonist, as IG-88 and Boba had issues back in the day in regards of bounties.
B) Cad Bane: His return in Bad Batch was mostly to prepare us for his debut in live action. As an older man, Cad Bane will mostly advice and guide Boba in his path to become the main ruler of the Under World. His fate could be seal here as he sacrifice himself to save Boba from a trap (or like some people believe, they recreate the duel from the Clone Wars).
C) Black Krrsantan: A great character from the comics who can be introduce here and then later on be used on Kenobi. I had a strange vision of Ice Cube's son portraying the character. Another ally to Boba in the cause.
D) Valance: The first time that i saw the character, it reminded me of terminator. He is getting love in the comics as well, so seeing him is possible.
E) Durge: Another character who was brought back in the comics. Great bounty hunter who appear in the 2003 Clone Wars. I am not sure if he will be an ally or an antagonist of Boba, as he had bad thoughts in regards of mandalorians and clones (mostly explains his loyalty to the CIS).
F) 4-LOM and Zuckuss: I am not sure as the ongoing comics are telling the fate of this two. They could first be allies and later on betray Boba.
Now with the big baddie (and other potencial baddies as well)
2) Prince Xizor: With the Emperor and Vader dead, and without a strong Empire to challenge him, his rule as the leader of Black Sun is undisputed. Other criminal syndicates could make appereances like the Pykes, Crimson Dawn (still need to wait until the comics are finish to fully see the fate of this syndicate), and the Hutts (either Jabba's son or Zorba (Jabba's Dad) trying to regain whats left of the power).
Now as external note, another character which i want to discuss:
3) Omega: With her i feel that it is too soon to see her in live action, as her story is not conclude in the Bad Batch (and it takes the momentum to don't fully know what happens to her as we will know if she appear here that she is alive at the end of the series, leaving the mystery behind).
4) Plot: It will likely resembles the movie "The Expendables". A group of veterans (and child heroes actors) teaming up against a common enemy. Going full in depth to the Under World (getting vives from Solo), and showing the changes in Boba's behaviour, as he is now a honorable man. It goes with the line "All killer, no filler" said by one of the actors.
5) Ending and Season 2: We will get an ending scene like Mandalorian Season 1: A figure in brown robes watching something or someone in the distance that we don't know yet (to leave space for theories), and a little glimpse to his right robotic arm. Yeah, this is who do you think it is, as he is coming back.
Another character for Season 2 will be Han Solo. Both Han and Boba had history way back before Episode 4 while working for Jabba. In this season, we will get a new confrontation and later on, Boba will befriend Han just like in the EU.
Leave down below what are your thoughts on this. I wrote a post a while back with my treatment of the saga mving forward (if done right, content for more than 15 years with the first 5 being Thrawn, then 5 years up to 2030 with Abeloth and finally 5 years wth an adaption of Legacy comics (Talon, Krayt, Cade)) It is a way more shorter post of every season, thus why i try to go more deeper with BoB.
https://starwarstheory.com/THEORY/posts/FLL0bd0oW4rruYI7laRR