What was so ruinous about implicit returns? That's one of the things I missed most when leaving CoffeeScript. ECMAScript only partially adopted it (single statement fat arrow functions) which probably muddies the waters for people trying to learn and understand the language's behavior.
Since it's optional for the caller to use or assign the return value of a function, I don't see much problem with functions defaulting to returning something. Maybe it just fits with my personal preference of functions returning a value and not having side-effects..