In a perfect world...
I'd like to have a stage rack setup with a rack mounted split snake and a digital monitor board. Send a technical ryder to the venue ahead of time saying that you'll be doing your own monitoring via wireless IEM's and explaining the system. We show up with our rack, plug everything into our split snake, plug the back end of the snake into the house snake and pull up our monitor mixes from last time we played that room. Instant setup.
We're actually working on doing this via Laptop with protools and a Profire 2626. Everybody goes direct into the split snake, which splits into the 2626 and the FOH snake. Run our IEM's from the outputs of the 2626 and firewire to protools. Protools handles the click track fed back into our monitor mixes and FOH gets the same signal they would get normally. We'd even be able to record the show. Hopefully we'll have most of it built next week!