*** The first third of the episode, with Galen and Picard, is stupendous. Excellent acting, good writing, and superb direction by Frakes.
*** The idea at the basis of this episode is nothing less than monumental: what are the origins of life not only on Earth, but in the known universe? I can't imagine a more important question to ask, short of how the universe itself came about.
*** The question is too big to be answered in 44 minutes and then dismissed the way the characters do. Perhaps the writers did not realize the implications of what they were writing. Such a discovery would shake the very foundations of the Federation, of Picard, of... everything. It pains me to see it dealt with like the chase for a simple artifact.
*** The episode literally screams intelligent design, which is a new low for Star Trek. Roddenberry, a humanist, wanted the show to be based on hard science, and this is the direction that ST has always taken (especially in Voyager, but also numerous times in TNG). To see an episode that shuns scientific method and embraces ID views is sad to say the least.
*** Picard and Crusher, among others, are supposed to be scientists but carry out scientific method very poorly... not to mention that the dialogue about DNA in the laboratory is full of technical mistakes.
Overall, this episode is "painful to watch" because it sets too high a bar and then can't jump it. It should have been a two-parter, and even then it would have been difficult to integrate it with the ST world (unless the final answer was along the lines of, "it's impossible to know an answer," something that most of the public, especially Christians, would of course not accept). In short, this episode should have never been made. It is simply too ambitious.