If anyone's still watching this thread: I've posted what will likely be the final version of these avatars. Here's the link:
http://www.efn.org/~kellys/tosranks.zipAnd here's what they look like:
As you can see, I went with gold after all, but a more tan/sandy gold than I had before. (Believe me, I watched several episodes and sampled a lot of screen-caps to try to get it just right. Ironically, it's pretty much the same shade as I had at the very start.) I also added a little more orange to the red, and lightened up all the sleeves just a bit. (All those well-lit TOS rooms.
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) Finally, I tightened up the spacing of the Commander and Lt. Commander stripes, and added Lt. JG (as seen in "The Naked Time").
Just for comparison, here are a few examples of the first batch:
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(Quite a difference, huh?)
I'd edit the previous posts to get rid of duplicates and dead links, but I've passed the time limit - sorry. Thanks to Fab for his help (and for goading me to take the time to do it right) and to everyone else for your kind words and suggestions.