A little off topic here, but I found a leader with bad synergy for his UB, at least: Zara Yaqob.
He's creative, but his UB is a replacement for the monument. If I play a creative leader, who gets +2 culture per turn for each city, I usually completely ignore the whole mysticism/religion line until I either get a religion spread into one of my cities and I want to spread it further, which means I need Meditation for monasteries or monotheism for Organized Religion, or I don't get any happiness resources, which means I need to go up the religious line until I can get Monarchy and HR.
He's creative, but his UB is a replacement for the monument. If I play a creative leader, who gets +2 culture per turn for each city, I usually completely ignore the whole mysticism/religion line until I either get a religion spread into one of my cities and I want to spread it further, which means I need Meditation for monasteries or monotheism for Organized Religion, or I don't get any happiness resources, which means I need to go up the religious line until I can get Monarchy and HR.