RD, since bipes this size won't have much more than 10 inches of unsupported span anywhere, the wings can be built lighter. Thin the wings down somewhat. 4 ailerons is the only way to go. To keep the combined MAC [of the 2 wings] at the same point as your monoplane, the lower wing will need to move back a little. Increase the tail feather area, give it a manly rudder. My Goldberg bipe has most everything set at 0-0-0, except the O.S. 1.20 needs right thrust, a 1/2A engine swinging a 6x3 won't. Sounds like a great way to start your building season!