I went back to the online critique group I'd left before, because despite the frustration I'd experienced last time, there was a single comment on the first chapter of Summer-set that helped me rewrite it into something that could sell. (I would thank the critiquer, except I had the impression that she disliked the story. See how negative criticism can be more helpful?) I'm hoping for something similar for "Gutter-wing" — all it might need is just one person's throwaway remark to trigger some blinding authorly insight.
I think my earlier mistake was in expecting something similar to an in-person or static membership critique group, where you can depend on getting the same level and quality of feedback each round. It seems this site might be better suited for what I think are called beta reads: gathering first impressions instead of in-depth lookovers.
I've got the first chapter up now — in fact, this spurred me to fill in a few holes that my non-linear writing method had left — and we'll see what comes.