I had an interesting discussion with friends and there are some more things, that I think, Wyll is missing.
A lot of characters have trauma due to not being free , yet here is Wyll, still literally being a slave to Mizora and he gets not much to say. Same with his physical changes - he did literally suffer through all torments of hell, which I doubt even Abdirak would find amusing, and his whole body gets changed in the process and he doesn't get a scene around it, just a bit of dialogue, which mostly makes fun of it. Menawhile we have a whole scene with Astarion over his looks and Shadowheart over a changed hair colour. And before those two fangroups jump at me: I don't want to say, take that away, I just think, it's sad, that we literally see, what a companion goes through and there is not a similar moving scene for him afterwards. I know Wyll is the stoic type and shrugs a lot of stuff away, but I think, he just had the worst day imaginable and should have had more than a short comment afterwards. What he experienced, should traumatize everyone.
I just put it out here in case, there is the slightest of chances, there might be something to be done about it.
I'm glad you brought up him going through the torments of the hells. "Wyll burns in the fires of Avernus; the lightning storms of Dis strike his flesh. His soul passes through each layer of the Hells, gaining their essence - and their torment."
People really downplay what Mizora puts him through. She doesn't just permanently change his body against his will, she physically tortures him. You're right, he really needed a scene or 2 more where he gets to talk about his feelings.