elvis - I've found that sleeping on the bean bag has reduced my hip pain a fair bit this time around, haven't needed to decamp to the saggy old studio couch. I also have a pillow under bump and between knees, which helps with the SPD - but I think for me the thing that helps most with the hip pain is having something that helps support my back. With DS it was the back of the studio couch; this time, it's held in place by the bean bag (beanbag is to stop me being flat because of the awful reflux in the night). So - you could try packing a bunch of pillows or whatever behind your back as well, see if it makes any difference?
I don't move much when I'm actually asleep either, but I'm finding I can get through the night with usually only one turn over this time around, which I couldn't with DS. Mind you, once that piercing hip pain starts, I have to turn over - it's impossible to ride it out or go back to sleep. I hate it!