So, without further ado, the FlatJack:
It is an acoustic, build on an electric platform. Very like the Godin (thanks, guys, for mentioning Godin's when I was looking for advice on this project), except it is completely hollow, unlike the Godin's I tried at the store.
So, the specs:
Body: Single piece of Mahogany,
Soundboard: $15 spruce from LMII -- their cheapest board.
Neck: Port Orford cedar/lumberyard oak sandwitch (24.5 inch scale)
Fretboard: Madagascar Rosewood
Amplification: K&K pure minis
Finish: Tru-Oil.
I hollowed out the body blank to 6mm, except for the upper bout, which I left at 12mm. For the back bracing, I just them carved into the blank instead of gluing more pieces in.
The neck is a set neck, glued into a routed pocket in the body. Several times simpler than fitting a mortise and tenon neck into a standard acoustic.
The results are quite gratifying. I can reach all 22 of the frets easily. One side effect of the electric style neck is that the action is very low, and very easy to play. Very similar to playing an electric. And (with the back panel in place) it doesn't feed back, even at levels that caused complaints from my neighbors in Tierra Del Fuego

Tonewise, it is as you'd expect. A bit like a parlor guitar, with good highs and reasonable mids. But the low notes suffer quite a bit from the small, narrow body. And there are considerably fewer overtones across the board than on my OM builds. That is not necessarily a bad thing. One problem with the OM builds is that my voice (which is weak and mid-rangy) is easily covered by the guitar unless I capo up about 6 frets. This guitar leaves enough of the midrange unoccupied that I can hear me sing. Nice for me, not so much for anyone else in the area

I welcome any comments, questions, and critiques...
--Paul