If performance matters more than looks, then I suggest you all read Wainfan's PAV report at the Facetmobile site. Very interesting stuff. He makes a convincing case that you can make a safer, simpler, lighter aircraft with less labor, out of flat structural panels. Or, for a homebuilder, perhaps riveted tubing a la Facetmobile. The structural panels idea, I think, might lend itself to a "Smoothmobile" without too much trouble if the outer panels were fairly thin.
His PAV would outperform a 152 on 80 hp (instead of 110), have very benign stall, and gobs of room inside. I recall the useful load was above 500 lbs. I'd say it was vaporware if it was coming from someone else and a smaller prototype had not flown. The Facetmobile did 110mph and 750 fpm with useful load of 250 lbs and horsepower in the 40's. Empty weight was only 370 lbs. Wainfan didn't discuss this, but from a lecture of his it sounds like the plane was spirally stable. It would fly as slow as 33 knots, which might be nice if you had to land in a bad place. (And he did, which is why it's not in the air right now.) Also a lot of airplane in front of you and to the side if you hit a tree. If it was SUFFICIENTLY spirally stable, that probably means that you could fly into a cloud and come out the other side without instruments if you didn't do anything super dumb.
Anyway, I think that, unless it's too ugly, this would be a very promising approach. And I think the smoothmobile version wouldn't be ugly.
I just had an idea recently for a 103 compliant aircraft that ought to be very light and fairly easy to construct, but I'm keeping it under my hat for now. Inspired partly by the Skypup.
I hope the airfoil is not flat like on those foamies! That would probably generate only half the lift a regular airfoil would, and it would be structurally very weak unless you braced it with a gazillion wires. I think you might want to go a bit wider on the fuselage, or use an aluminum rectangle as the S2 motorglider does. The rectangle has a nice feature that it kind of lays out the whole fuse and you can bolt all the components to it. Have you seen the Cloudster ultralight? Has some features in common with your design.