at least a proper live should be done with a mixed cd (ok so far) and play some special parts live (melodies) or even tweak some knobs as live parts , thats what makes a live intersting , the more u do live the better , i improvise a lot of times , specially melodies and such. i pratice some stuff before i go into the stage. of course that its impossible to make an whole song like since there is tons of layers to play at the same time , but at least its always nice to make something LIVE.