Hello Dave,
Good to hear from you. I did purchase an A-37 ... didn't get it yet but it's on its way. I've been using a Ketron SD1 Plus and I'm starting to mind the weight. I sold the Casio some time ago, I do have a couple of Yamaha KX5's that I use occasionally with the Midjay Plus. Have you checked out the Roland Luciana or the Alesis Vortex? They seem to be reasonably priced, but they may not be enough keyboard for a player of your caliber.
Ciao,
Jerry