I've played piano since I was five, and percussion since I was twelve. I also tap dance in my spare time, and am teaching myself the harmonica with a kit someone got for me as a gift. Yeah, badass, right?
I thought I was going to be a musician for a long time, but as you said, wrldisquiethere, adding the creative aspect is really tricky. I'm good at feeling the necessary mood in the piece and playing it out, but back when I was adjudicated for my piano playing, I had a really difficult time with adjudicators who would try to help me by saying stuff like "Imagine a sunny field of flowers..." I'd be like "Please! Just tell me to play it more legato or quieter or something! You aren't helping!"
Also, even when I was a little kid (and by "little", I mean about age six or seven), I'd be a perfectionist to a fault. I'd get upset whenever I messed up. There were two piano recitals I did when I actually made audible frustrated noises when I screwed up chords. I love piano, but it would drive me up the wall to do it for a living.
And to answer the rest of your questions: I hate jamming, and I'd rather perform for others (I'd love to be in a cover band, or just play (and/or sing) solo; I do a killer version of "Fired" by Ben Folds that I found online

), but I love playing on my own, too; also, I like all styles of music to an extent, except for ones that
a. are too dissonant,
b. are sexist/racist/biased in any way,
c. have no melody (e.g. certain metal bands), discounting percussion ensemble stuff and good rap music
c. are generic/boring, or
d. are overly sappy (like Celine Dion or Barbra Streisand).
Favorite musicians/bands at the moment: Husker Du (later work, not hardcore stuff), Paul Simon, Genesis (all eras), Fleet Foxes, Joe Jackson, Emerson Lake and Palmer, Green Day, and Jethro Tull.
I believe that whole rant was repeated from another post I did on a different thread, but I don't care that much

p.s. 300th post! w00t!