Although I have unfortunately had several experiences with UA similar to the OP, I do have a few flights that really stick out in my mind as excellent. In particular, a FRA-IAD flight in 2007 with a Paris based crew (Is the Paris crew base still open?). Between a cabin full of businessmen and a surprisingly all male crew, my wife was the only woman in the J cabin. The crew paid her ridiculous amounts of attention (which she loved), and then thanked me regularly for letting them do so. Overall, really excellent, professional crew. I wish they were all as motivated and service-oriented.