Yep Naughty Nauticals is a trend-based collection, with all the blues, and then the three parter is as follows: Neo Sci-Fi is the main colour collection, with lipglass, nail polish, eyeshadow, sheertone shimmer blush, and so forth. Solar Field has the Solar Bits as well as bronzers. Future Earth is the skincare portion. Cool Heat is eyeshadow, slimshine, and perfume.
Vanilla is definitely the most popular pigment I would say, and I've been meaning to get it for ages (lucky me to have a freestanding two bus rides away) but I dunno...I'm loving Jardin Aires more because it's the bronze-y, so I can press bronzer.
As far as good ones to invest in...
Vanilla (even though I have ones I like better, it is a must-have)
Violet (very subtle, very nice in the crease)
Jardin Aires (it is LE but it is constantly repromoted...)
Golden Lemon (a nice, bright sunny colour)
Melon
Rose
Copper Sparkle
and any LE ones that you find appealing, or any good ones at your local CCO
You will have to go to your freestanding though and check it out because you and I more than likely have different colour tastes, so you can see what works for you.