Rather than try to do an entire new scene, would you consider doing the research that duktig flicka suggested in the library, and introduce one little new thing each time .... at a point in the scene where it wouldn't be expected.

I try to do that in our play. That way I don't have to think so hard that I get out a the zone, I have something to look forward to, and she has no idea when something new is coming. It doesn't have to be anything major, just something like ice at the right moment, or a new way of doing something .... do you use floggers? Why not change the pace?

Just a thought.