I can find an otherwise competent and creative work offputting if someone is aiming for pastiche and (in my very subjective judgment) falling distinctly short.

Yes, this is basically my issue — this is such a big risk in works trying to mimic the writing style (you get this with fic for TV/film canons where the scriptwriters have very distinct dialogue styles as well). I can appreciate well written book fandom fanfic as long as I feel it matches my understanding of the characters, setting, and important themes of the original, but as soon as it attempts to mimic the writing style and falls short, it's lost me, and I'd rather the writer hadn't bothered. If they get it right, of course, it's an added bonus.

Thanks for sharing the link to the once_upon_fic comm. I'll try to get nominations in before they close.