I like the idea and I'm currently working on something similar, but #ECD400 isn't even close to brass. This yellow color almost makes me sick. The hexcode that's usually called Brass is #B5A642: http://encycolorpedia.com/b5a642, which is very discrete and easy to the eye, yet contrasts well against black. Looks good all along its monocromatic scale, so it would be possible using it all over for an entire desktop theme, from bone white #eeebd5 to #0f0e05 which I would say is about the color of coffee beans. Then there's also #cd9575 which is called Antique brass: http://encycolorpedia.com/cd9575. Also pleasant and more towards red.

So please, keep working! You seem to be on the right track - but this one really looks... well, it's totally horrible...

One more thing: In NouveGnome grey there's no specific icon for the Chrome Browser, and on a monocromatic scale it's identical to Chromium. So I searched for a more traditional stiff icon - default Google Crome, black and white, no grey scale - and and fiddled around with it. Removed the black leaving empty space, then put the negative icon on the clean grey globe in NGg, which gave me a shaded grey icon with black lines. Then I just removed the black lines.

At the moment I'm trying to become friendly with GIMP, shadows, transparancey and stuff, then I'll try and make some kind of simple monocromatic brass icon theme. First project will probably be just getting a layer of #B5A642 on each of the icons of NGg, that would look good enough to live with for a few years. But I have a somewhat larger project too, where I'd use different images. Mostly simple and monochromatic brass, but with an ambition of adding a feeling of 1st Industrial revolution to the theme. I'd also like to put each one on a glossy black background and add a brass frame around it, to make them visible on light backgrounds as well as dark ones. I hope I can bother myself to making an entire desktop theme in mahogany with Victorian brass details and and lamps for buttons, glowing in prelight mode...

I've started some re-coloring now, using this theme and nouveGnome Steel. I found some setting in the Colorozize tool which becomes #B5A641 at a specific lightness. I also found the Colorify, where the exact hex can be set. It also appears that some fiddling with contrast and lightness is required to achieve the metallic look. Especially some of the round ones need a lot more contrast. I'm not completely satisfied. It doesn't look better than this one in any obvious way, only more to my my personal taste. Not terror yellow but rather some dull mustard tone. I want some metal shine that's not glass glossy. Somewhere between this brushed style and a polished lamp. Maybe a slight bit more saturated golden yellowish than my recent mustard tone. Real brass isn't really #B5A642, but rather pale yellow where it reflects light, and towards dark bernstein where it's in the shade.

There are some nouveGnome Greys that I don't like at all and I've found some decent alternatives. This is especially the arrows. Some of my own ones doesn't really play well with the general style of nouve, but I'll figure something out. The GTK window stuff doesn't necessarily need to follow the style of the program starters, maps and stuff. Top priority is making something that's discrete, easy to read, yet adding some color to the environment. Also, some aestethical unity is essential.

Then there are some issues with scaling. Some Actions icons become HUGE in some specific programs, taking up some 25% vertical screen space. It's the toolbar of Synaptic, the window opening when saving stuff from Firefox and the window opening in Caja after having made a Search, then clicking Open Folder of the one of the objects. Not yet sure how to deal with this, neither exactly what icons causing this. There are some appearing under different names. I'm making a map now for Actions icons scaled down to 32 x 32, but I don't think that will solve problems, still I really hope I won't need to scale every specific icon to six sizes...

Or maybe I should just get myself a life...?