Thank you so much for the response.
I'm not sure the word mutation would be appropriate here. The color vision could be either a characteristic of the collective species who took her, once upon a time, and turned her into one of their own, in which case her photoreceptors would have been altered during the process of assimilation, or an accidental result of the neurological damage she sustained when she was severed from them (which may or may not not have followed the same course as comparable neural degradation in humans because of the vastly different physiology).
To be honest, I was thinking more in terms of the disadvantages. I'd say she is already unable to perceive her surroundings normally - "missing" spoken language by 1/2 or more, risking going into shutdown from sensory stimuli of moderate intensity, including traffic noises and bright sunlight, or having difficulty converging sensory detail into the cohesive image of an object is not normal for any species - and the deficient or unusual color vision would take the lack of normality to a whole other level. In the narrative the character originated from (still in progress, in the final stages by now), this is a major plot point. In effect, she was incapacitated by the separation and would have had to return to her kind for reassimilation in any case, regardless of how the events might have unfolded, simply because she would have died otherwise. In that respect, she is the opposite of rogue drone characters like Seven of Nine on ST VOY or Frederick in "The Madness Season" in that she cannot survive outside of her collective (as in, literally), knows she belongs with them and misses them, but decides to stay separate on her own accord (because "others before self" - drone mentality, one might say, but in the better sense of those words). The perceptual disturbances would make it difficult to function on an elementary day-to-day level, which is a major part of her character development - we have had her grow as she adapts to an alien society and struggles with the practical obstacles waiting for her at every corner, often forfeiting her comfort or well-being in the process, and eventually achieves a balance between adjustment and self-sacrifice, on the one hand, and basic self-care on the other. Once again, the visual deficiency would give an additional dimension to this.
At the end of the day, I don't really think I will use the different color vision on the site, as it would entail a layer of complexity that is best left out, but it's always helpful to have some third-party feedback all the same.
That's an interesting idea, though I'm not clear on what exactly you have in mind when you say "magical". The reasons why we gave her the chromesthesia was that a) it appears to be particularly common among those on the autism spectrum and I happen to have it myself. This is why I'd rather not alter the "color profile" of the two names; the associations are my own, and while in theory I could attribute any color values I choose to the sounds, it's very difficult to ignore the imagery drifting in front of me as I write. It's a constant distraction and I don't think it would be worth that extra effort. (Of course, the human Hawa Najjar might have been a synaesthete as well, what with sound/color synaesthesia having a prevalence of 1-3 in 100 or so among the general population, but at this point it is almost irrelevant what she may or may not have been like)
Insect-like receptors could mean many different things depending on the particular species of arthropod you have in mind. If these are honey bees, she would have some receptors for UV wavelengths, but none attuned to the red portion of the spectrum, which would render her incapable of distinguishing most warm hues (red, rust, brown, ochre, orange). This is not really plausible, as differentiating between hues in this range would be necessary for survival and normal functioning in a habitat dominated by brown and rust-red rock, especially considering that the species had the same coloration due to the need for mimicry. Butterfly-like vision is more probable, but once again, there are plenty of different varieties to choose from. If you take the Japanese yellow swallowtail as a model, she should be a pentachromat with red, green, blue, violet and ultraviolet receptors; if you take the common bluebottle, she should have a group of three or four receptors for the green and blue sections of the spectrum, respectively, which would enable her to identify some exceptionally subtle hues of these two primary colors. I've been thinking about giving her an amalgam of the two, but haven't decided on the details yet.
This is important for the narrative; the exoskeletons of her species came exclusively in shades of brown, ochre and rust-red to allow them to blend into the environment, with some concealed violet markings, and appeared homogeneous and bland to humans, but if you saw them as one of their own, you would realize that the markings were a lot more sophisticated and beautiful and that there were other iridescent patterns elsewhere. The same would apply to Azila's exoskeleton, which would seem to be a boring umbre brown to the human eye, but, in actual fact, would have UV-reflective whorls.
I do have trouble thinking of Azila as faerie-like, regardless of whether or not she has insect-like vision and photoreceptors, but that might be just me.