I think that, regardless of your philosophy, you should bite the bullet, and arm yourself with a variety of midi's, and or MP3's. Wheras I play mostly arranger styles, I bring my laptop loaded with midi's, and played through a good soundcard and Notation Composer. They are set up as lead sheets and appropriate reg's are keyed to them. I then can play over them and or sing them.

This way, I am covered for the unexpected and sure can provide a better variety as it is called for. I also use MP3 for cover dance tunes.

Bernie