Not really. The author doesn't leverage any kind of static typesystem, which would at least mitigate some of the warts. He's chosen Node.js instead of leveraging the browser, so no free visualization layer for doing anything interesting with, unfortunately.
> Have you worked with a JS language for any extended period of time?
Most of my day job is working in a really, really big Javascript codebase. I can say with confidence that the language is something that we're absolutely stuck with, and I still have no idea why somebody would implement a pedagogical database with it (well, then again, they haven't; they've implemented a key-value store, which is trivial).
To offer an alternative, they could have chosen something boring but everywhere like Java, which is just as accessible to those with less experience. Then they'd have the possibility of doing fine-grained parallelism, file access, designing abstractions that fit within a statically typed language.