Glad to see people enjoying the classics!
As for me, for a long time I have been using vintage IBM keyboards, starting with the IBM Model M 101, then the IBM Model F XT. After all the two-tone beige boards, when I started with Topre-switch keyboards, I favored a black case with white/gray keycaps.
Most recently, I got a RF 87u 55g black and put a new set of blue Topre caps on it -- but just the alphanumeric keys. The mods, spacebar, F-keys and top portion of the navigation island are still black, but I've swapped out the black arrow keys for blue ones. It's kind of like an inverse anniversary edition look, and I like it very much.
Now I am thinking of getting a HHKB Pro 2 Type-S, putting the switches into a black case, and swapping the 45g domes for 55g domes from a 55g RF. This should be close to the ultimate Topre-switch board for me. (If the HHKB had a steel plate instead of case-mounted switches, I think it would be even better).