@domonoky I did read (or at least search) the manual, and the problem with creating a dynamic playlist is, as I said in my post, that the number of tracks exceeded the max allowed in a playlist. The database has yet to initialize for me without failure, probably because Rockbox seems to have issues with .ogg files that have ID3 tags (the default used by my CD ripping software). If I can find a way to convert ID3 tags to ogg comments, maybe it will become an option for me.
@alexp Thanks! I can now create a playlist with all my music on it. It takes about two minutes to build, though, and has to be re-built whenever I add new music, so a true shuffle feature would still be nice. /me makes a note to check the applications list for something that does this.
Anyway, thanks for the responses!