I'm kinda in the same boat. I picked up a second 67' Cutlass Supreme. I usually like to stay with the factory colors. But this one was Champagne, a light gold color, with a white vinyl top and black interior. The other one was Antique Pewter (med. gray) w/ black top & interior. I was going to use a late model Chevy truck metallic gray on it. Maybe with some black accents. (????) Oddly, both had been repainted blue.
And the second one had a coat of rattle can black primer over it.
Anyway, have you checked the paint code on the car? It might be a nice color.
Reds look good on the 67's. As do maroons, I saw a maroon w/ silver top one on ebay recently. The silver covered the top down to the side body line rather than a vinyl top look. It looked pretty good.
To be honest though I'm leaning towards a blue, maybe 69' Trophy Blue. Maybe blue & silver or dark gray.
Picking a color is hard. That's why I like to stay close to factory original, it's just easier!