I don't have a tagger so I had to go through each and every song and put down which genre I wanted as I was uploading it.

This isn't necessary. For mood playlists, you create them how you want, and put whatever songs in them you want that list to contain.

If the music is already on your empeg, you can put that song into multiple playlists without wasting space on the unit. I personally have a few top level playlists for 80's, Hard Rock, Techno, etc and in there, music organised into artist playlists, and subdivided still into CDs.

Spend some quality time in emplode getting things exactly the way you want. To date, the empeg is still the only MP3 player out there to allow you to put your music where you want it, and not how the device wants it. Also look into jEmplode if you like the predifined playlists for artist, genre, album, etc. We commonly call those soup views.