From a shooting perspective, the best choice would be the easiest color on the eyes that doesn't also conflict with any ball color. Example, shooting the 8-ball on black cloth... uh, where is the 8-ball? Oh yeah, ya gotta look for the arc of light to find it. So, even if I am a "green" fan, the depth of hue is relavent. From a decor point of view, tan cloth on natural wood tables has neutrality allowing it to combine nicely with just about any room, and green, not so oddly, has a similar result.
Blue??? It's all the rage in most pool halls, and brightens even the dreeryiest of hole-in-the-wall rooms (you know, the kind that one could stick to any of the walls or furniture or their shag carpeting), but I wouldn't have blue in my house... I'll never paint my billiard room walls any shade of blue, complementary or not. Having said that, it is good to note there aren't any light-blue billiard balls in a typical rack or pool room. The other down side of lighter colors is simply that they would be easier to mark up or stain (read that as "more noticeable").
Final note... Green is good. Simonis Green, or English Green... and speaking of cloth... is there a UV protectant in Simonis cloth?