It's probably a niche interest, but do you know if anyone's working on a Rust equivalent of Stroustrup's Design and Evolution of C++? I found that book a huge help in grokking the "why"s behind the language, and gaining some degree of mechanical sympathy with it.

I appreciate that the vast majority of Rust's D&E happened in the open, so most of it's probably still available, but it's been a long and twisty road since Graydon's initial public post and picking out a coherent narrative from umpteen separate slowly-linkrotting fora would be no small task.