I choose durability for sure, although power is a nice bonus I think visibility would be an important for orientation. You lose orientation, as a beginner is pretty easy, especially when things go south. With the plane spiralling to the ground because of loss of orientation a beginner doesn't know or has the reflexes yet pull out of most problematic situations. So power or handling will just drill it further into the dirt. And I have crashed many planes with dihedral, the plane won't fly itself because of dihedral, and for some who build, it becomes a crutch. I have seen some build like more dihedral will make the plane last longer for some reason. I don't really like dihedral on any planes anymore.
@Wildthing seems to have taken a new liking to excessive dihedral on his new Mustang though
. That should be an interesting maiden to watch