Sure, but maps are still bolted on. That's convenient, but it's not interesting. The interesting question is, what would a language that is to maps as Lisp is to s-expressions look like? The OP is the first person I know of who's tried to answer that.

It's an important question because maps are flexible and flexibility is important for exploratory programming, which is nearly all programming. If there exists a language that is as regular and programmable as Lisp but organized around maps rather than lists, that would be a big deal.