Your Redstone_dark is by far the best dark skin for me.
It's beautifully shaded dark, yet there is enough contrast in the bright white text to make it superbly usable.
I love the way Music Explorer song lists pick up the dominant color of the selected album cover.
Borderless, unshaded drop downs take some getting used to, especially on black backgrounds, but now I like them!
The light blue line around popup menus distinguishes them nicely.
Only one enhancement request IMHO so far:
Please make "# tracks" text, which appears under each item in the "Album Artist" sidebar, more legible. The very light gray is barely visible even at a reasonable display contrast setting. Same for "# albums" under each item in "Artist" sidebar, etc. This problem is present in every dark skin I've looked at, so maybe this font style is not accessible?