The Java specification is actually a fairly good specification and also covers a great deal of the runtime (of which Scala gets a free ride).
The C specification is 500 or so pages.
IMO the Go specification is sorely lacking in details (albeit I must confess written in a much more modern and pithy way). It also doesn't have legacy baggage. This isn't to say Go is bad or good but you shouldn't base your decision on the length of the spec (particularly when formatting also plays a large part).
BTW if you are looking for close to the best of both Go and Scala (an in between) take a serious hard look at OCaml. Yes OCaml multicore is not done but it is coming. And in ref to the authors mention of being explicit IMO OCaml is the most explicit language I know (ironic given it has incredibly good type inference).... Oh and for completeness its specification is 657 pages. I actually learned most of the language by reading the spec.