Just a bit on the "purpose and direction" part: (I may have said this earlier...if so, sorry...memory sometimes begins to go around 60.) Over the years, I've come to see UU as more of a shared methodology (or attitude) than a set of fixed beliefs. We are not the sum-total of seven "principles," but ideally those principles reflect something deeper. Whether it's "a religion" or not is really not the point (except in legal matters of course). At its best, I think, nothing could be more "religious", however. It's a "way of thinking" about what's ultimately most truthful and most important in life...about what really should be religion's highest priorities, and how to try to incorporate some of those priorities into our lives.
Over five centuries, this "stubbornly protestant" attitude or temperament in religion has led us in the direction of a faith in personal "soul freedom", in the importance of private judgment and of utmost honesty between what we say we believe and what we actually believe (...and hopefully in how we "live out" those beliefs), plus a corresponding humility about the honest limits to "what we actually know" (or can know) as imperfect human beings.
But the main point, I think, is that it's a deliberately evolutionary faith...a work in progress, where both imperfection and a desire to improve and grow are equally "hardwired" into our "method." It's been going on for centuries now--that effort to "reform" the religious quest for truth and meaning, to separate the best parts of religion from the more trivial and petty. Jefferson called it the distinguishing the "diamonds in a dunghill." A little later Rev. Theodore Parker was a little more diplomatic in describing it as the "transient and the permanent" in religion. Whatever we call it today, that "sifting process" is still going on, still trying to be as honest as possible about it, still imperfect, still a "work in progress"... and always will be. (Hopefully, after all this time, we're at least getting a little better at it.)
Ron