By numeric type do you mean a type implementing numeric operations? I agree, it's weird they haven't just whacked an interface on that.
And when are we getting an "unless"? It's way more readable than "if (!(some complex condition))".
Oh and null coalescing with member support. "y = x != null ? x.prop : value" is way too verbose.
At least you have the option of out params. I have to use Java every day and the only real option is return classes.