It's a very tough one for me, so I will just give my opinions of the collections (at least the big ones
N Collection: Hate neutrals. PASS!
Fafi: Loved some of the lip stuff, but hated the packaging. Also one of the MA's tried to sell me on the Fafi 2 eyes, and I am SO glad I passed.
Heatherette: LOVED THIS. I love most collections that have a pigment with it, and this had glitters as well! I didn't like the looks of the Trio 2, but the Trio 1 was actually quite nice (I am wearing Mood Ring today). If there is one palette colour that should become a permanent, it's Mood Ring.
Dazzleglass: Although this was just lips, I adore this to death. I got 6 total, and they are the best gloss ever.
Naughty Nauticals: While I wasn't really into the shadows (I don't like darks), the pigments kicked butt as did the lipsticks. It just felt kinda...small. I dunno though.
Neo Sci-Fi: This actually was a really nice, wearable collection when you strip away the packaging and so forth. Almost anybody could find use for all the eyeshadows, and anything to repromo Pink Grapefruit is A-OK. And Electro? *swoons* I would have gotten a LOT from this collection-Femme Fi, Evening Aura, Expensive Pink, Soft & Slow, Scatterrays, a backup of Electro, a backup of Pink Grapefruit, and a couple jars of the VAE-but I had bank trouble.
Cool Heat: So underrated. I love blue and green eye looks and this had amazing things. I hit pan on Solar White very quickly! The lip products were also very wearable and I like the Slimshines-they aren't just for summer.
Colour Forms: While I didn't like everything, I loved the packaging, and I could have bought almost everything from it. The pigments were really nice, way better than the Overrich ones.
Electroflash/Sonic Chic: I'm a fan of the MSF's, but not exactly a blush person. Also I have heard everything about the MES, and while I would have loved to get a couple, it's nothing really I felt I just HAD to have.
Starflash: Good colours, HORRID texture. I am seriously considering B2M'ing my Sunset B., because I have In Living Pink and it's not only a better texture, but it actually has colour payoff.
Cult of Cherry: Despite the fact that it is not my thing, I actually did like some of the lip stuff. It's a good collection for many people, however it's not my thing.
Ungaro: BO-RING.
Of everything already released, I would have to say it is a toss-up between Heatherette and Colour Forms. Colour Forms gets the edge though simply because of Oh Garnet being in the warm lips palette.