I have been playing around with this in Zillions, adding Capablanca pieces and found it is a very interesting design. I am planning on having this game modified to the IAGO Chess System framework, complete with Capablanca pieces in it, in the next few weeks.
I am doing this entry separately to discuss it, as I happened to also stumble across it while working on an attempt to port Grand Chess to an 8x8 board.