I do tend to follow a certain arc to each evening's music; the first one is a rolling piece that evolves gently, then I tend to dig a little deeper into some more complex harmonies, then try a rhythmic  thing that moves and builds. After that I often do a more simple, easy thing, then maybe another energetic piece, or a very somber dirge. Whatever the particular flow, I try to have variety and some development over the course of the set. Now watch me mess with it now that I've described the "usual"! Hey, whatever; enjoy!