I agree that episode 3 was better and tighter. I was quite happy with it until it started up with the theories of Paul Stamets, the mushroom guy. He's really knowledgeable about fungus and it's potential uses, but.... I went to a health food convention (don't ask) several years ago and Stamets was the keynote speaker. Most of his talk was interesting, he's smart with creative ideas about the uses of mushrooms... but the last 10 minutes of the talk he went off on some weird tangent about the nature of reality and theoretical physics. He sounded like a stoned teenager saying "Whoooah, dude. What if, you know, the universe is a cosmic mushroom, and like the structure of space-time is connected like a giant fungus, man."
And I cried a little.
Star Trek has always had an uneasy fascination with sketchy pop science. I hope they drop this plot thread soon.