Obi-Wan Kenobi is getting his own series on Disney+ and many Star Wars characters from across the galaxy can return for a role. Set between 2005's Star Wars: Revenge of the Sith and 1977's Star Wars: A New Hope, there are multiple stories that can be told with the Jedi Master.
The Obi-Wan Kenobi series takes place in a unique point in the Star Wars timeline, making many characters from the Age of Republic and Age of Rebellion available to it. Obi-Wan himself appeared in the first six Star Wars films covering his younger years all the way to his time as a Force ghost. Given all the Star Wars characters active during the time of the Kenobi series, there's a ton of familiar faces fans could feasibly hope to see on the show.
Ewan McGregor is returning to the role of Kenobi and we last saw him at the end of Revenge of the Sith promising to look after a newborn Luke Skywalker. The next time audiences see Obi-Wan in live-action is at the beginning of A New Hope. Older, wiser and played by Alec Guinness, not much is told to the audiences about what Obi-Wan has been through during his exile. While material outside of the mainline films filled in gaps, there is a ton of untouched Star Wars timeline for the series to explore and a number of fan-favorite characters could play a part in filling those gaps.
Owen Lars
One of the most interesting characters that could use further exploration in the Obi-Wan Kenobi series is Owen Lars. Uncle Owen was seen adopting Luke Skywalker at the end of Star Wars: Revenge of the Sith. Owen's raised Luke Skywalker far from anything to do with the Force or the Jedi. This was not only done to keep him hidden from the Emperor, but also because of Owen's view of Obi-Wan and the Jedi as a whole. The mention of the name Obi-Wan by Luke in A New Hope caught the attention of Owen and Beru, with Owen proclaiming him dead and calling Ben Kenobi a crazy old man. It is also revealed that Owen did not want Luke to leave the planet with Obi-Wan on a "damn fool idealistic crusade" like Anakin did years before. Jason Aaron's Star Wars comics run further supported this by showing Owen blame Obi-Wan for the death of Anakin Skywalker.
Owen does not like Kenobi hanging around Luke and believes his activity in Tatoonie will eventually expose Luke to the Empire. The two seem to have a lot of animosity towards each other. The Obi-Wan Kenobi series would make for the perfect opportunity to delve into Owen and Kenobi's relationship as it deteriorates to the point of Episode IV. Joel Edgerton has said he would love to reprise his role as Uncle Owen, an opportunity to put those two actors together shouldn't be passed up.
Luke Skywalker
Young Luke Skywalker would be an excellent character for a (preferably small) role in the Obi-Wan Kenobi series. In A New Hope, Luke Skywalker clearly has met Ben Kenobi before and recognizes him right away at the start of the film. This would mean that Obi-Wan met Luke at least once before during his childhood. We know the two met a few times, as one story reveals Obi-Wan Saved Luke and his friend from a Krayt Dragon and another shows him saving him during a scuffle with some of Jabba the Hutt's henchmen. While Luke had no clue about Ben Kenobi's real name or Obi-Wan's affiliation with the Jedi or the Force, he was still familiar and on good terms with Old Ben.
If a young Luke Skywalker did appear in the Obi-Wan Kenobi series, it could be a great opportunity for the show to explore the first time these two iconic characters met. Obi-Wan promised to look over Luke from afar from the moment he was born and knowing Uncle Owen's disdain for the old Jedi Master, there could even be multiple episodes worth of story to explore. Even if the two do not physically meet in the series, the comics showed that Obi-Wan wrote journals for Luke to read when he got older. It is possible the series will cover moments of Obi-Wan working on the journals and could even use it as a narration tool as the series progresses.
Darth Maul
Darth Maul is a fan-favorite character that can definitely appear in the Obi-Wan Kenobi series. The two have battled many times in canon across live-action and animation. The first time the two battled was in Star Wars: The Phantom Menace. In it, Maul killed Obi-Wan's master Qui-Gon Jinn and the battle ended with Kenobi slicing the Sith in half to his apparent doom. The two would meet again in Star Wars: The Clone Wars animated series where the conflict between them would grow even more as Maul kills the one true love in Obi-Wan's life, Satine Kryze.
As seen in Solo: A Star Wars Story, Maul is still very much an active threat during this era. The events of Solo open up multiple avenues for the Kenobi series. Unexplored plot threads saved for future films in the spin-off franchise are now open for Obi-Wan Kenobi to tackle. Appearances by the Crimson Dawn crime syndicate alongside Darth Maul could potentially be a series villain level threat. While we know that Darth Maul eventually dies at the hands of Kenobi in season 3 of Star Wars Rebels, the potential to further explore their relationship (or even re-explore their final conflict from a new perspective) would make for a highlight in the series.
Jabba The Hutt
Presumably set mostly on Tatooine, the Obi-Wan Kenobi series will likely have the Jedi dealing with the scum and villainy of the desert planet. Jabba The Hutt is very active on Tatooine during the years the series takes place and his presence on the planet could be explored further. Obi-Wan Kenobi has never been the type to stand idle as people are in danger. Instinctually being a Jedi and needing to help others, Obi-Wan's interactions with the people of Tatooine would be interesting to see.
Kenobi showed his dislike for Mos Eisley in A New Hope to Luke Skywalker and Jabba The Hutt commonly uses the area for his operations as well. The character appears many times in the original Star Wars Trilogy, which prevents Obi-Wan from actually defeating the villain, he could meet the character or attempt to destabilize some of his influence in the region. As a major crime lord on Tatooine, even if Obi-Wan doesn't come into direct conflict with Jabba, it's more than likely the giant slug's presence will be known.
Bib Fortuna
If Jabba The Hutt appears in the Obi-Wan Kenobi series, Bib Fortuna would not be very far behind. Bib served as Jabba's majordomo for several decades. The character appeared as early as Star Wars: The Phantom Menace after an older version of him was originally revealed in Star Wars: Return of the Jedi (where he met his end at the Great Pit of Carkoon). Because of his closeness to Jabba The Hutt and his presence on Tatooine, he could have a role in the Obi-Wan Kenobi series.
Fortuna has definitely not had enough screen time considering his importance in Jabba's crime organization, and learning more about his influence on the desert planet would greatly flesh out his character. Obi-Wan has had moments where he faced some of Jabba's henchmen in the comics and adapting those stories could lead to fans seeing more of Bib Fortuna. Whether Jabba The Hutt appears or not, Bib might make for an interesting cameo for Star Wars fans to enjoy.
Bail Organa
Senator Bail Organa is a unique character in Star Wars mythology. He is one of the very few people who know about the existence of Luke and Leia, the events of Mustafar, and the whereabouts of both Obi-Wan Kenobi and Yoda. Played by Jimmy Smits, the character had roles in Star Wars: Attack of the Clones, Star Wars: Revenge of the Sith and Rogue One: A Star Wars Story. While it is unclear if Bail ever met Obi-Wan Kenobi after the events of Revenge of the Sith, he would be one of the few allies that Kenobi can actually trust at this point in the timeline. In a situation where Obi-Wan could be in danger of being exposed or caught by the Empire, Bail Organa could be his only hope. Even if the two do not physically meet, seeing what Bail Organa is doing during this time period would be interesting and could even lead to a cameo from a young Leia as well.
Qui-Gon Jinn
Qui-Gon Jinn died in Star Wars: The Phantom Menace but his story did not end there. At the end of Star Wars: Revenge of the Sith, Yoda revealed that Qui-Gon had begun to learn the path to becoming a Force ghost. The ability would later be used by both Obi-Wan and Yoda in future films. During his years in exile, Yoda instructed Obi-Wan to try to commune with Qui-Gon and learn for himself, so with Liam Neeson saying he's open to playing Qui-Gon again, there is a great opportunity for the master and student to reunite one more time.
Aside from learning more about the lore surrounding Force ghosts, the dialogue between the two Jedi would be the best part of it all. Qui-Gon is the one who chose Anakin Skywalker and saw the potential he had. He is also the one to make Obi-Wan vow to train him before his death. Having the two discuss the events that unfolded and their respective rolls in the creation of Darth Vader (and thus the destruction of the Jedi Order) could make for a few dramatic moments. Obi-Wan is presumably in a broken place during this part of the timeline. Everything about his way of life had been destroyed and he internally blamed himself. Showing Ewan McGregor's Obi-Wan communicate with Liam Neeson's Qui-Gon during this point of his life would add so much to both characters and elevate Star Wars canon even further.
The Obi-Wan Kenobi series could end becoming one of the best live-action offerings from the Star Wars franchise. Set in a vastly unexplored part of the Star Wars timeline, multiple characters from across the galaxy are available for the series to explore. From allies and villains that Obi-Wan has personally known in the Prequels to his first interactions with characters from the Original trilogy, Disney+'s Obi-Wan series can be the true bridge between multiple eras of the Star Wars saga.