I am currently beginning the build on my new Model Tech Joss Stick with a 68" wingspan. However instead of monocoating it I want to go with a natural stained wood finish. Here lies my problem, can the wing tip caps that are supposed to be covered by monocoat be left off and have wing tips more simular to that on the Hangar 9 "TWIST"? Ive seen discussions of "Sticks" being built upside down and with less dihedral but never anything more. Any feedback would be greatly appreciated.

I'm sure someone will give you a more scientific answer, but I don't see how that would affect the plane much. You will loose a very small percentage of wing area. The more square edges might make it more draggy at high alpha, and it might want to tip stall a little more... but theese affects I think would be so small I don't think you would really notice.