If you care about a rich standard library, and static self-contained executables, I would strongly suggest Crystal. I have used both Go and Crystal, and the latter is much more productive as well as simpler. It’s standard library is richer. See, for example, the things you can do with strings with the provided functions. I used to love Go. But after some time the verbosity got tiring. I moved to Crystal, and there is nothing I miss from Go. Two big caveats: 1. I dont work in a big team. 2. My main use case is a web-backend.
Since you mention Clojure: That's useless for me, because it runs on the JVM. One reason to use Go is exactly that it produces static, self-contained executables that don't require any heavy infrastructure.