I have a suggestion for future development: it would be nice if there were a place in the tune file for some limited commentary or info beyond just the name of the tune. Extra nice would be if the commentary could be surfaced in the app somehow.
Here is a bigger, pie-in-the-sky suggestion: provide, in the app, a way to browse the user songs repository and to download tunes. I see this has been discussed before.
I've been spending a silly amount of time creating tunes for the app. Much fun!