There's some songs (Like King of Sorrow and the vast majority of the Sleddin' Hill album by August Burns Red) that have frequent BPM changes. How do you translate this into Rocksmith? You can only set an average BPM. Thanks!

You can create a tempo map in EOF.  Here are a couple tutorials:

 

http://customsforge.com/topic/5099-how-to-sync-your-beat-map/

http://customsforge.com/topic/5136-using-beat-markers-to-sync-in-eof/