I cut the top wing panel into two sections simply because it's easier to fold and glue 1/2 of the wing at a time. Folding and gluing the entire wing at one time is hard to manage, but if you think you can comfortably do it, by all means go for it! As for mixing the elevators, on a hand launched combat plane, it isn't worth the trouble or extra weight. I've never done it, but this experience comes from two fellow combat pilots who have done it. But if you were to add landing gear and use it as a sport plane, the mixing would be usefull for ground handeling. I should also add that if you were to make a HOR into a 4 channel sport plane with LG, it would more than likely need more power than a .15!