I disagree about 3D. My contention was a hover trainer-sport model that has a high resale value and is really tough(a little heavy) it could be sold to another beginner(without electronics) when it was outgrown.
I think that all RC helicopters will be flybarless within 2 years. The cost of the multi-axis controllers is bound to come down, The Gaui unit is already around $200.
thick shafts, flexi blades, flexi tail boom?