I've gone back to the monochromatic version, at least for now. It just has more of that classical feel to it and the sky doesn't compete as much with the central figure. I widened the aspect ratio from 1:1.5 to 1:1.25 for a 16"x20" final print, though I'm starting to wonder if I might need to tighten up the framing somewhat. Started sharpening the rendering on most everything from the ribcage up. Pulled in her right shoulder a bit to correct a proportional error and adjusted the angle of her right forearm for better balance. Intensified her halo and the glow coming off her wings. Getting there slowly but surely.
Here's an almost full-res close-up on the more refined upper body. I'm pretty happy with the overall texture that's coming through.
And finally, here are a couple of hair style variants, one with ears covered and the other with her hair drawn back behind them. Haven't been able to decide which I like better. Opinions?