I read this back to back during my Richard Bach phase.
For most readers, stopping with Jonathan Livingston Seagull is probably enough. If one is still adventurous, this is the next and perhaps final stop.
It is the story of a reluctant messiah, and in some ways the book seems written for its ending. That ending lands well on a first reading. It has the compact force of a parable.
But on rereading, the messiah himself becomes harder to accept. A character shown as kind, and capable of bringing dead insects back to life, still chooses to traumatize the protagonist and, through him, the reader. That now feels weaker to me than it once did.
No doubt, it remains a thought-provoking book. It is just one of those books that changes shape when read in one’s forties rather than one’s twenties.