RE: help on balance
Thirty percent is going to be to far back, To acheve any kind of positive pitch stability at all 25 is going to be at the limit of aft CG and more than likely around 20. Vortex generators anywhere are a moot point.
Another potential problem are the vertical surfaces. They appear to at about 50% MAC and would contribut nothing to yaw stability, in other words the airplane really won,t care if its pointing in the right direction or not. A better place for the fins would be back and just outboard of the rear trailing edge cutouts.
John