This seems like a major increase in quality compared to past attempts. And with long term coherency too, check out those 5 minute tracks.

And if that wasn't up, we even got an additional mode that lets you provide a melody of your own and ask for an arrangement. Should be very useful for composition.

Assuming that these results aren't cherrypicked or otherwise misleading, I'd be very excited to try to make music with an open replication of this.