What about support for using Golang or C# packages? That'd be handy.

Interesting read about NIM-

https://www.quora.com/Why-hasnt-Nim-Nimrod-become-as-popular...

Key points:

- Nim lacks official support to multiple inheritance or interfaces (as that in Java) or mixin (as that in Ruby). It feels uneasy when implementing common design patterns, which is important for middle to large-sized projects.

- The error messages emitted from Nim compiler looks a bit obscure. Sometimes you have to guess or google to comprehend what really happens in your code.

These seem like pretty good problems compared to common annoyances and caveats in many other languages.