Favorites:
1. ENFP - I love their combination of intelligence and enthusiasm. Once I get out of my shell we often find we have compatible values and understand each other's thoughts and feelings well. I find their dominant Ne stimulating and naturally more expansive than my own thinking, and it helps keep me from sinking into FiSi mode. My constant need to filter myself around people is much less severe around them. They also have a lot of curiosity and insight, two things I greatly value in people.
2. INFJ - insightful; intelligent; inspiring. Familiar and completely foreign, and that's what makes for an interesting dynamic. We sometimes have similar but not identical values and opinions but completely different thought processes, and it's interesting to see something familiar through a different frame.
3. ISFP - Very similar to me in a lot of ways, but the Se/Ni vs. Ne/Si difference makes us different enough to keep it interesting. I find many of them quietly perceptive, but they aren't the type to assume they know more about me than I know about myself. We also often have similar tastes in art and music. Despite the hipster stereotype, I find most of them pretty unassuming.
4. INTJ - (Only if they have well-developed Fi.) Mature, intelligent, very insightful in multiple areas, and often not as arrogant as people assume. They strike me as genuine truth-seekers who want to do something productive with their knowledge, something I greatly respect. I would probably have to develop stronger Te to make it work, though.
5. ENTP - Only if they have well-developed, genuine Fe. I love their intellectual creativity and individualistic nature. Quirky like xNFPs, but with more of an edge. Zany but not loopy - I actually find they have great common sense (and yes, these were definitely ENTPs, not ESTPs). Often well-read.
6. ENFJ
"Unfavorites":
1. ESFJ - Completely different values, very little understanding. They sometimes drive me up the wall, and I think the feeling is mutual.
2. ESTJ - " except we don't dislike and annoy each other as much.
3. ESFP - Horrible, horrible match. I've found a significant portion of young ESFPs I've known to be prone to causing problems for themselves and then refusing to see it, instead blaming it on other people. Compared to a lot of types, I've noticed they have a tendency to be hugely overconfident with their inferior function (Ni).
4. ISTP - I don't usually dislike them, we just have very little in common. They tend to misunderstand me and I assume it goes both ways.