a "flying drag farm". I like it

The tail is about 9% of the total wing area but it is 4 chords back so it has a bit of leverage.
I would go for all 3 wings thin and slightly cambered at +1 degree and a flat plate or thin symmetrical tail at zero, and a CG about 20% to 25% (my formula gives 23%) of the wing chord.
and the best of luck keeping it all lined up and warp free.
Alasdair