Black Honey Almost Lipstick by Clinique is a really great purple/violet on me (also NC15), Black Violet l/s by Clinique is also good but not as intense.
For MAC... Lure's the only I like for purples (that are not borderline black) but it's been discontinnued. I think Craving looks too pink, same with Captive. Rebel looks pretty cool for a plum though.