While some of the features MoonScript provides are very interesting, I'm not sure it's really needed as much for Lua as CoffeeScript is for JavaScript - Lua is a rather nice language on its own.
Lua is actually pretty verbose. The MoonScript codebase is about 1700 lines of MoonScript and it compiles up to 3k lines of Lua (and that's without whitespace and comments)
Things like classes, comprehensions, and other syntactic sugar really do help with writing concise and easy to read programs.
Things like classes, comprehensions, and other syntactic sugar really do help with writing concise and easy to read programs.