Again, thank you!

[1] As for how vs. why, I'll have to think about that.

[2] Evidence is we arose from simpler origins. The role of small proteins now is unlikely to be the same now as it was at the start.

[3] You write: For example, I struggle to see how a philosophy that sees every human being as the product of a random process without any purpose, can give any intrinsic worth to people.

How (or why) can you think that way? What's the purpose of a flower? What's the purpose of a rock? The worth of a thing is not how it was created, but the thing itself. There is innate value in all of nature, every aspect of it, regardless of how it arose. You don't need God to believe that. If human beings arose by random molecular interactions, then how incredible were those molecules and interactions! It's all fantastically beautiful and I'm not devalued in the slightest.

[4] I don't need or want a vaccine against death. I plan to die. I don't look forward to it, nor do I dread it. My life is about my life, not about my death. Whatever happens afterward, I'll find out. Or I won't. I have LDS relatives who seem obsessed with what happens after death. They don't understand me, and I don't understand them.

[5] Just an anecdote. I was once very impressed by a young Christian girl who came to our house with her family to celebrate Passover. They were (presumably still are) pretty zealous Christians. Her dad and I were friends and coworkers.

During the meal/service she wanted to (and did) participate fully. She wanted to know everything. There was no question that anything would change her beliefs. Or ours. Changing beliefs was not the point. Getting to know each other, and experiencing each other fully as fellow human beings, was. Accepting others, despite thinking differently, or having different traditions, is way more important than getting things "right."