I don't know about "might be worth it" part, and I don't think Go is success is because of it's concurrency model. Instead, I think Go wins because it can get thing done quickly, in one stop.
The concurrency model has been designed to help achieve that, and the huge battery pack came with the language is also for help achieve that.
I'm not discouraging you from design your language, though. In fact, I could be very happy to see a new language which can give me all the benefits that Go gives me and at same time just ... simply be a better language.
My ideal language (in my opinion) is a combination of Go and Rust: Big standard battery (Help me get things done and encourage to it's ecosystem)(&BTW, it don't have to be in the standard library), and fearless programming (Help me avoid mistakes).
Sadly Rust don't want to have a big battery for some reason :(