I just thought this might shed a little light as to the Bronze debate.
These three statements in particular
"All but one or two were silver-chrome vacuum-plated. A couple were Gold toned bronze plated. The Gold Cylons represented the two-brain "C2" Officer Class and were first seen in the sixth and seventh 1978"
"Oberon's costume is one of only about a dozen made (4 gold, 8 silver) and most of those have been mounted on mannequins; leaving only a few Cylons still roaming the Galaxy."
"EC" WARRIORS OF THE ELITE CLASS: "C2" Command Centurions who were Executive Officers to the Imperious Leader. They had gold armor with black bands to indicate their rank. Vulpa was of the "EC" Class. He was banned by the Imperious Leader to the ice planet Arcta for opposing the Leader's views. He was later killed when the "Ravashal Pulsar Gun" on the Planet "Arcta" was destroyed by a small band of human Colonials in the episode "The Gun on Ice Planet Zero".
This is about the best evidence I could find that a bronze actualy did exsist as he does mention it in his recollection.
Maybe there were plans for the use of a bronze and the introduction of more of the cylon higherarchy but they never made it to that stage of the show before it was canceled and the bronze was never used or breifly used in the castle scene in "The Young Lords"
Ya know ...Up close, Gold is Gold and Bronze is Bronze ...why would Metz mention a Gold tone Bronze? and it sounds like they made 12 special suites for "Oberon" (4 Gold and 8 Silver) If Olberon was a C1 promoted to a C2 then silver to gold would be appropriate and maybe the "Gold Tone Bronze Chrome" was a way of distinguishing the difference between Olberon and Vulpa as Vulpa was EC and definatly Gold?
When he say's (4 gold and 8 Silver) maybe he is refering to the Gold tone bronze he mentions earlier in the page?
Just speculating on my part though
If I find more I'll post it