That sounds AWESOME from a technical perspective. Is there a reason that you're doing a client/server thing instead of just having "offline mode" be the default, though?

For a solely single-player game, it seems to me like being able to host everything off of a static fileserver instead of a Scala server seems like a scalability win for you and a bandwidth win for users. I don't doubt your choice and your tech stack (you know way more about your project and its needs than I do!), but I'd be super-curious to hear more about the reasoning and process.