I agree that complete wing sheeting is not necessary - it will only add weight. I would Spar the top and bottom of the wing to allow wing sheers and also a strong wing joining point (with a dihedral wing, eh). Sheet the leading edge of the wing to the main spar locations - keep light; build to fly. Use film on the wings. Tail dragger or tri-cycle gear? By default you'll have steering if you build a tail dragger, ie, rudder alone or wheel attached to rudder. Control linkage for tri-gear can be little more tight to install but having the extra weight up front usually makes the model easier to balance, ie, models have a tendency to build, tail heavy. IN any event - you need to be able to steer the model during takeoff and landing if for no other reason than to counter act engine torque. Use balsa planks for fuse and tail feathers. One final thought - CHECK BALANCE BEFORE FLYING!