This is easier to word than ones I don't like!
I love terrestrial Utrics, there's something about their growth habit, variety, and various display possibilities that fascinates me. I also like anything with unusual color, whether it's in the flowers or foliage. I'll be easier to phrase this through categories....
-Drosera: I like the pygmies, especially the orange flowered ones, tuberous, and oddly shaped ones a lot. They're fun to photograph with back lighting.
-Nepenthes: Lowlanders and highlanders. I like the dark ones with bright interiors or odd features. I'm very partial to the ones with screaming reds, thick peristomes, odd shapes, and smaller sizes (I do like the giants too). I doesn't matter if they're bulky, fat behemoths, or pencil thin to me. The more variable the species the better for me.
-Dionaea: I'm not partial to the ones that can't trap food, but I love the color variants, like Maroon Monster. They grow very well for me, so that's a plus.
-Sarracenia: I prefer pure species, but the more unique hybrids make me drool. They're native to my area and easy to grow as well. They also add some curiosity to the front yard, too. Big or little, doesn't matter here. I like creating hybrids as well, I have a nice one in mind for the spring.
-Utricularia: Already expressed my feelings towards these, and I can't wait to expand my collection.
-Cephalotus: I need to grow these, they're too cool looking.
-Darlingtonia: Too much work to grow where I live, but I like the way they look, and they're worthy of a sculpture.
-Heliamphora: Not my favorites since it's hard for me to tell them apart (I can't see green), but the dark colors and hairy of H. pulcella are awesome!
-Pinguicula: I killed my primulifloria, but I like the looks of some of the Mexican species. Their succulent growth interests me as well, I just have no clue how to grow them.
Personally, I like keeping a variety of plants. That way one one group goes dormant another one wakes up or hits full stride. Something is always going on this way, and the collection is always interesting.