I think what sirkingchase is talking about is more in line with what Palantir was doing, (http://cushman.net/2006/11/06/palantir/) along with some emplode like feature to add new songs. To me, that seems reasonable.

The initial steps to adding more music would be to look into the fid system, and just get a new song onto the player without worrying about the database. The player will rebuild it's own database if needed. Once you get the basics working, then you could try tackling the database part on the Android device and send it over. I imagine a more modern ARM processor would be able to rebuild the DB much quicker then the one in the empeg.