In general, light colors suit smaller cars better, and dark colors suit bigger cars better.
On the other hand, cognac and ivory interiors are usually best combined with dark colors, especially dark blue and dark green. An exception is light ivory with cognac interior which is a very nice and subtle combination.
As said before, dark colors require a very high quality prep and work, and are more dificult to keep clean.
My 280SL has a cognac interior an is non metal tobacco brown, with brown hard ans soft tops. I like it, though I believe tobacco brown suits a W108 or 109 better. Also, I do not have nor plan to fit A/C and this color is a torture in summer. I'm consirering painting it ivory when time comes.