Ha. This is quite true. I wish there were an (obvious) way to build languages on top of Go's runtime, in much the same way as Clojure/Scala/etc run on the JVM.
I think having the Go runtime be specific to Go is what makes it such an effective runtime.
Why?
And more to the point: binding an alternate syntax to the runtime wouldn't make it any less specific to Go.
A lot of Go's GC is tied up in the semantics of Go. An alternate syntax would indeed be an interesting idea.