While it would be an "interesting" gadget to have, an AOA just isn't necessary for Mooneys, (or any other GA aircraft), the more I think about it. In carrier ops, it's critical for setting the aircraft at the proper angle to ensure snagging the intended arresting cable, or for use in extreme high AOA flight such as during ACM.
As far as which types of planes are easier to fly, (GA or Tactical), they each have different characteristics that need particular attention to fly them safely and effectively. However, there is no comparison between the complexity of systems used in a tactical jet compared to the simplicity of a Mooney. Also, the MISSION for which the tactical aircraft is flown is where the largest difference exists between the two. When I was flying in the military, you would either be flying some sort of tactical training flight, (ACM, AWIs, Low Level, etc.), or your flight was an "Admin Hop", meaning you were just motoring between two points. Now that all I fly is GA, all my flights are "admin hops". Not that it isn't enjoyable. However, as I recall, most of my military flights could be compared to high pressure athletic competitions, where afterward, you are exhausted, soaked with sweat, exhilirated, and ready for a beer! (Jake, former Marine F-4S pilot, T-2C instructor Kingsville).