"* Lack of parametric polymorphism means there's no useful higher-level functions like map, fold, etc."

This is one of my problems with Go, too. This will add line after line of repeated code in the long run. Time will tell.

I find the opposite on the error handling. The lack of exceptions is one of the few things I like about go. I just wish they had done error handling correctly instead of the stupid kludge they put in because "durr what is an ADT?". I agree that the lack of parametric polymorphism makes go essentially useless, I just don't understand how python is any better. It also lacks parametric polymorphism, and in fact polymorphism period. It is a unityped language.