The last principle in the Zen is “Namespaces are one honking great idea – let’s do more of those!”
I do not understand what “let’s do more of those!”. What “those” means? “Zen”, or “namespaces”?
If it means “namespaces”, what “let’s do more of those!” mean? “Produce more with namespaces”, or “Use namespaces more”?
I’d say it’s definitely referring to namespaces.
As to what exactly ‘more namespaces’ is supposed to mean exactly, I suppose only Tim really knows 
I would say it means do more “namespaces” and “honking great ideas”. Namespaces are just one idea, we need more. At the same time, we should make more use of namespaces, because it is a great idea.