Way i see it, red, white, yellow and black are all acceptable colours for a Ducati, as they are for a Ferrari. Although strangely, about the best colour was the metallic pale blue of the Pantah. Whatever. But for me, the yellow colour is associated with the Supersport bikes - 748, 749 and nothing else. I think the black 999 looks much better than the red one, apart from the red and black R models. The Senna - red frame with grey bodywork just looked weird, whereas orange with grey would have been well cool.
You should never have asked us in the first place! That'll larn you. A good call I suspect. I think the red Monster looks better, plus the carbon baubles show up better and you're bound to end up with those.
Well if they're matching, they're going to be red, aren't they? Doh! You can go black - cool and invisible and end up in hospital Multi-coloured - stay out of hospital but look like a racetrack refugee. Perhaps best - red white black - à la Ducati leathers. Visible but not Valentino Rossi style.
In my opinion if it's Ducati superbike - it should be red, any other model I prefer black or black and gold combo... but each to their own etc...