I like the look very much! I agree once the washers are oxidized and discolored it will look even better.
I tried my first etch on an enclosure a few days ago. I did manage to get what I wanted which was nasty and baaaad. I encourage you try, it was fun and much quicker than etching circuit boards. I used permanent staetdler markers and acrylic to block out the acid. Work pretty well, I'm sure toner works much better.