A co-worker of mine published something I found very nifty today: https://crates.io/crates/document-features
It is just a small proc-macro that parses the [features] section of your Cargo.toml and puts that information nicely formatted and with any comment you made attached into your crates documentation.
Many crates have really poor documentation for the features they offer, maybe this little crate can help to improve the status quo a bit.