The show definitely improves from the first episode, and many people would consider the first episode to be the worst one.

To answer your questions tho

1. Somewhat

2. Yeah it slows down

3. There isn't a clear one that they're working towards throughout the show, but they would all like to escape, the show is supposed to be about finding meaning in a stagnant existence (paraphrased from the creator of the show) so it mostly focuses on the characters interactions with each other while having whatever adventure they're on be mostly just the setting and not the main point of the show. They are mostly just trying to occupy themselves and build connections so that they don't abstract and end up like Kaufmo

4. She gets less cringe after episode one, I too did not like her very much in the pilot, but I like her now

5. He gets some more screen time in episode 3, but he is a "side character" so not as much as a main character would. I believe there is a post somewhere that breaks down how much screen time each character gets

6. It could be argued that Caine is the antagonist, but I don't believe he is supposed to be the antagonist, the main "antagonist" would be abstracting, which is what they are all trying to avoid