My favorite individual feature of this language, reading through the spec, is the explicit tail-call statement:

  sp2_help( bits32 n, bits32 s, bits32 p ) {
   if n==1 {
    return( s, p );
   } else {
    jump sp2_help( n-1, s+n, p*n );
   }
  }

Clang has a similar thing now, but it's an attribute not a language keyword. There's two things I like about it:

First, it communicates intent better. For someone not familiar with the principle of a tail call or a sibling call, thinking of it as a goto is easier, and is what the compiler is actually doing underneath to prevent a stack overflow.

Second, it allows for the compiler to see if the tail call is well-formed right then and there. It would then flag an invalid one as an error instead of not optimizing the tail call. This prevents any surprises at runtime.

For a higher-level language than C--, it'd be fun to call this explicit tail-call statement goto, and have no other form of goto statement. It's just as powerful in expression as the classic goto while avoiding its pitfalls.