Clipping a flighted CAG negatively impacts their psyche. Flying also helps keep their cardiovascular system healthy.
All birds love to land on 'perches' that are high up. There's not a whole lot you can do about it except to put something on top of it that may prevent her from landing there while she's out.
All 13 of my birds, which include 3 CAGS, are flighted and not one of my birds has ever plucked.
Vannah has her flight feathers. Her previous owner clipped her wings once about 20 years ago. She didn't start plucking, but she was so offended by it, he never did it again.