Aerobatic is usually taken to refer to the ability to do predetermined precision aerobatics as in aerobatic competition.

Maneuverability (the ability to change speed, direction and orientation quickly) is what you want in combat. In my opinion, 12 degrees of dihedral on each side will give you just about all the maneuverability that you will want. When you go inverted you won't stay there long and neither you nor your opponent will know which way you are going to roll out. The spiral stability imparted by dihedral will allow you to take your eyes off your model briefly to look around without loosing control. This is a big advantage in combat. It also reduces the pilot work load which is another advantage. There is no particular combat advantage to being able to do axial rolls or to do sustained inverted flight.