Well I enjoyed the middle section, but I'm definitely getting the same feeling from Dreamer/Taylor/Rose/whatever-her-title-is that I did from It's Not Wrong. Which is, the more that character is included in the story the more my enjoyment of the story dies. I don't even know why, it's just like QAylor's adventures are all so fun and then including Dreamer is pure buzzkill.
I think that entirely depends on how Taylor is treated by the story/author. If she's just pure crack or a manic pixie dreamgirl, then yes, the story would suffer. But if it were taken seriously, with the serious implications of events factored into the story rather than used as comedy, it would work very, very well.
Because the fact is that Taylor is the traumatized one, not QA (EDIT: As Alivaril has pointed out, QA is plenty traumatized herself; however, I think QA has more of an ignorance problem and less of a "social anxiety while also being very lonely" problem). And Taylor is a serious person (especially since she had humor beaten out of her life ruthlessly at Winslow); while mind-altering drugs can excuse that temporarily, it shouldn't be used for (much) humor and shouldn't be a lasting thing.
One of the running themes of BAAHSSCQ is of people who have suffered gradually coping with and overcoming their past trauma, from Anna to Yukari. It's also about people who have learned to cope with and overcome their own trauma helping those who have not yet achieved that--just like at Instructors Meyer and Leonhart becoming the unofficial cool aunt for Anna, or Instructors Washington and Vivas showing themselves to be true peers to Anna in terms of skill and insight (and giving Anna a connection and sense of belonging--as well as feeling more like she can rely on others rather than always being the one relied upon).
I'd definitely like to see those themes applied to Taylor. Remember, Taylor is someone who desperately yearns for friends and social belonging, but it also plagued by low self-esteem and social skills that have atrophied and been sabotaged by bullying. At the same time, Taylor is someone who will give her all to self-improvement (though she has a harder time overcoming social trauma); we saw that all the time in canon. She gave Bitch her own cut of a job's money just to get frank answers from Bitch about her mindset and thoughts...so that she could better connect with Bitch and be better friends. She'd constantly innovate with her power and train her own body and fighting skills to become as capable as possible. She'd be extremely resourceful with whatever she had against formidable opposition.
As much as QA is the alien learning to be better at being human while also being a crazy innovator, Taylor is kind of like the human who would dedicate herself to self-improvement for combat skills while also seeking companionship/peers that she could trust and fight alongside.
Amusingly, I think Taylor would get along extremely well with Kojirou, because Kojirou is very easy to trust (he's a very earnest and simple person, while also being kind and outgoing. He works hard for self-improvement. He's also a loyal and forgiving person) and get along with. And Taylor would be the kind of person to dive headlong into Shuri's relentless training regimen and
like it, because she loves self-improvement and is dedicated as hell.
