Don't forget the "Green Bug". I was sitting in a cafe patio overlooking a fairly busy 6 lane divided road. Cars were busily moving in both directions. Almost all were white, black grey or silver. Occasionally a red or blue would pass... then I saw it. The Lime Green Bug (Volkswagen). It was quite a distance away as it captured my full attention, a drifting green lime peel in the ebb & flow of the traffic stream, then floating by in slow motion. It was all a little surreal. The Green Bug was the most important focus in the whole moving landscape.
I would never consider driving a Green Bug, or anything like it (well... maybe a Lava Orange Porsche GT3 RS !!!) but I will always enjoy seeing the occasional color surprise ... and in the appropriate setting, so will your client.
Color preference. You've had it since you were a child. It will probably mature with years, widen in scope but probably always retain original preferential residue. As a designer, it's important that personal preferences remain under conscious control. A client's color preferences blended with your intuitive creativity will point color in the proper direction... if you let it. Developing a color palette is very similar to diverse community of children... different ages, colors, sizes, desires, talents and all the other minute details community. Letting them grow, develop & find their place in your palette will usually result in the most stimulating & beautiful solution.