This is full of good news. Esp. nice that the first priority stated is to make programming easier for Go users (pragmatism above all). I like that they're looking at generics again, but it doesn't sound like that'll land any time soon. Overall a really nice thoughtful overview of what the Go team (or this member of it anyway) is thinking. Not sure I understood the immutability bit.
This looks really great, is anyone using it for a real app? It does require you to build in support for a given service though - would be perfect if someone made a package that let you self-deploy instantly to any of the popular services or VPS providers, so that users could instantly self-deploy. This was the promise of containers but it doesn't feel quite ready for that yet.