I’ve recently gotten a Mustang Omega and attempted to fly it post 1.0. It was horrible, unresponsive and did feel right. Felt like i was flying in decoupled mode all of the time. I first though it was my joystick but after much research and trial and error I uninstalled and reinstalled Arena Commander. Works like a charm. Just putting this out there for anyone who has the same issues. Below are the common symptoms that I was having.
Mustang model changing colors (also may have been an older model not removed from older version of AC)
Unable to get into mustang in Hanger module
Unable to accelerate properly
Unable to turn properly in coupled mode
HUD works when in 3rd person view (there should be no HUD)