Rich,
Seems that you could scale down some of the1/2A ships just keep the total weight to around 9oz or less using either foam or creative balsa construction. Build it as a Flat Winger from 1/8" with spruce main spare and watch the battery weight. Since these are indoor ships I would add a bit more engine offset maybe 3-4 degrees to hold it out, try and have the motor thrust line go through the vertical CG so the offset only produces a yaw moment. I would use the pusher prop to keep things tight on the outside maneuvers. Fly it like a dead calm day and step back to avoid hitting the wake.
Where in Florida could we fly them indoors for say 45 - 55' lines?
Best, DennisT