I'm only going to say so much because my solution to this very problem is where I make most of my programming money but I will say this: the slave machines only have one scene, I prefer Net Broadcaster to OSC, and Applescript is your friend. I think my biggest piece of advice is to very clearly definite the parameters of functionality for your system before programming so you can build a set of patches that aren't going to require you to spend a huge amount of time switch between computers/screen sharing windows. Doing a show with two playback computers where you're constantly switching back and forth to make programming changes during tech is workable but once you get much past that there is no way to avoid significantly holding up the tech process every time you need to make an ostensibly simple change.