My question is: What sort of FRONT PANEL functionality does the empeg have that can do my simple genre/artist sorting so I can use playlists for something else?

Create as many playlists as you want, you will not hit any performance problems. I currently use 2 soup playlists using Jemplode (see my post here on how to create those playlists) but I could just as easily have 10 more playlists sorting my songs by mood, genre and sub-genre, etc. Those would have to be manual playlists since you can't have multiple genres or such (maybe the comment field could be used for this?) but you get the point. Sort and organize any way you would like.

Ok, FAQ me once, FAQ me twice (I really have to figure out SOUPs); but for some reason, I never fully understood "tweaking" a playlist by artist, genre, album, etc. When you press one of those remote control buttons as the playlist is running, what EXACTALY does it do? Enqueue songs? Resort the playlist? Shrink the playlist?

When you tweak (let's say by Artist) the Empeg searches forward in the current running playlist to find the next matching Artist. Then it SWAPS the next song with the matched one. So say you are listening to song #5 by R.E.M., and song #6 is by Radiohead. You press tweak by Artist. The next song by R.E.M. is #45. The Empeg will take the Radiohead song in #6, put it in slot #45, then take the R.E.M. song and place it in slot #6. If there is no more R.E.M. songs, it will do nothing.

I set up a Popup menu in Hijack to do the Tweak Order functions without the remote.