I've been thinking about how the Pariah blades were made into plowshares by being repurposed as theater props, and how that logic might be applied to Bolaire for him to become part of an afterlife ritual. My theory is that it isn't just about Bolaire choosing to be a museum curator, or even choosing to be a person (though I think it is about that, too.) It's about how he chooses to relate to his hosts.
Think about it. What made the Pariah blades into plowshares wasn't about their physical form. It was about the purpose they were being used for, and about their relationship to their wielders. It was about Shadia looking at the blades and thinking of herself as an artist and the blade as her artistic medium.
Thus far, almost all of Bolaire's relationships with his hosts have either been his wielder as the enslaver/abuser and himself as the victim (the way the soldiers wielded him for decades, as we saw in the cold open of episode 13), or with himself as the enslaver/abuser and his host as the victim (Aubrus Drime, Lux Adora, Rulius Mercanaud, etc.) We've now seen what the experience of wearing him is like when he is in abuser mode: he keeps them imprisoned in the audience of a theater, controls how much access they have to their bodies and senses, and can use the lighting and architecture of the mind theater to torment them.
However, we have also seen glimpses of what wearing Bolaire might be like when he is neither the abuser nor the victim.
When Tyranny put on Bolaire, he was a voice at the back of her mind, and could cast spells to supplement her own magic. When Misha Undragore put on Bolaire, he got the kid glove treatment. Bolaire recreated ancient and long-forgotten plays for him, while discussing their artistic merit. He served him great wine, which had the same effects and taste that real wine would have had. He was able to do all of this while simultaneously navigating a complex discussion externally about what had just happened in the city and what plans to pursue next.
I also think that Bolaire can do even better than that, because we know from the Schemers' Tale Gate interview that Taliesin has a specific concept in mind for what would happen if Hal were to wear Bolaire. Given how much Bolaire loves Hal, I think we have to assume that he would experience something even more special than Misha did.
For Bolaire to become a plowshare, I believe he is going to have to imagine new concepts of who he could be for the people who wear him. So, based on what we know about Bolaire's capabilities, here are some of my thoughts about the good things he could do for his hosts, not just Misha or Hal, after he has some character development:
Given his virtual reality-like capabilities in the mind theater, and all of the knowledge he has, Bolaire could be the ultimate teacher, giving his wearers a sandbox in which they can try out sparring techniques, magic, or anything else risk-free.
For someone like Azune who has experienced a great deal of loss, he could provide his mind theater as a space to recreate and remember the past.
Given all of the illusion magic Bolaire wields, he could even allow his wearers to externally project as artistic illusion all of the things they can possibly stage and imagine inside his mind theater.
He could be a protector, worn by the weak and vulnerable, providing them magic and cover to survive in difficult circumstances.
Bolaire said of Misha: "His heart rate is very stable." He is also capable of getting his hosts mind-drunk. If he has a lot of insight and/or control into the bodily workings and mental states of his wearers, he could potentially help diagnose illness, numb pain, or heal in other ways.
Given that Bolaire is a warlock patron (currently his own patron), and we know that warlock patronage can prevent the Tachonises from taking people's souls, he could protect people against the Tachonises specifically.
I have a strong sense that this is the direction that the narrative is going with this character (unless of course Bolaire dies or Taliesin decides to Make Him Worse), so I'm really excited to see what plowshare!Bolaire ends up looking like. But first, Bolaire needs to realize that a) the way he's been behaving has just been a continuation of his life as a weapon, not true freedom or transformation, and b) he wants to save the halflings from the Piper's Down.