For a rescue it's in pretty good shape...lucky you. I have been pondering rescuing one from another office buddy, but I am afraid that once I get it back to a bit above merely surviving, she will want it back and end up killing it anyways.
I am a newbie so I don't really know much about the cutting back, but if it were me, I would cut down the flower spikes to the base to give the plant a rest since it will now have to get used to you and your conditions, but I am sure others with more knowledge will chime in soon