After thinking it over, Think I have decided to go with the 9.7cc piston configuration, mostly for the extra compression, and less work required with the crank.
Currently have a cam being spec'd by BTR, just waiting to hear back. Also talking with Comp Cams about their conical valve springs. Not a lot of info on them, but seem to get a great ticket for a build like this.
Basic Parts list for now, subject to major change.