I will be the lone dissenter on ceiling fans in kitchens. Not sure why everyone thinks they're taboo. I have them in two kitchens, and they serve their purpose--moving the air around in a room that can get very stuffy.

I vote for no rocks. Unless you live in a very arid climate, they are seldom site appropriate, they tend to heat up excessively and retain that heat, often causing stress to the plants, they add nothing of value to the soil and are far more difficult to keep debris and weed free. An organic mulch is a much better idea.

Of course you will do whatever you want but I will reiterate that rocks are a very poor idea. If you persist with the rock idea, then neither of the two options you presented would look very good. A standard gray tone would look much better than those colored examples.