Hey Ken. My wife's parents attend both the Unitarian Universalist Church and are liberal Quakers. My wife was raised as a super liberal Quaker.. We were married under the care of the Society of Friends, the Quakers. So I have attended both often and yet am neither. I was raised as a Roman Catholic. But today I have sort of a freelance spirituality that leans heavy on Buddhist traditions. Meditation as we discussed a while ago has been a big help to me.
I have found the UUs extremely open and welcoming. I like that each Sunday they have a different spiritual speaker. They are also really engaged in social and civil rights issues here. I have a lot more experience with the Quakers. They really seek to see the God in every man and woman. Open and non dogmatic theologically. Peace and justice and non violence are important values in their community. Strong emphasis on community. Their services consist of an hour of silent meditation where you just sit quietly. Since I am familiar with meditation practice this comes easy. Both communities are open and welcoming. Neither will try to convert you, it's not what they do. Don't expect any prying into your personal life. I have found spiritual support in both. Wish you the best in your search. Dave, a fellow seeker.