Nim should look very attractive to Python developers. It's a good looking language that has positioned itself in a good market: static typing, looks and feels like scripting (not verbose), and almost systems level (has GC).
I haven't got any experience with Go development, but from those I know that use it, I hear nothing but promising things about Nim. "Modern" is a word that gets used.
Between Rust and Nim, we're starting to see some really clever new languages that fix common pain points. Both of these are so neat it makes me feel as though we're in a programming language boom right now.