Well, I'm not much of a dancer, so that's not important; anything with a beat will get me to tap my feet or something.
Thinking is good, a line that stays in my head for days and applies to life is a plus.
It's good to try new things, but nothing too drastic.
No surprises is also good; I like a key change or something, but that's about as crazy as I need to get on a daily basis.
Trippy? No. Fast? Sometimes, but not too much so. Complex? Not always, but it doesn't necessarily hurt.
Sad? Only if it's genuine. Happy? Only if it's genuine. Sloppy? No, but loose is good. Tight? Only if the emotion is preserved.
The lyrics and the music need to complement each other; the lyrics are only there to tell what the music is already saying for those who may not be able to communicate in that language. Really, lyrics are often completely un-necessary for master notesmiths, but master wordsmiths can really use them to advantage.
Other? I like really filthy music. Not explicit lyrics, mind you, but I want to hear the expression in the guitar, I want to know that the drummer is sweating bullets, and I want to know that the harp is screaming in pure agony.
