So heartwarming! I had the same experience with my white-eared conure, although it took me a little longer to figure out that I shouldn't be clipping his wings.Where I live, the bird community is still really big on wing clipping, but I know the difference it made for Charlie. He definitely became less aggressive and more confident. Definitely more confident. It was almost like watching a little kid grow into an adult overnight.
Before he could fly, he was very needy, always begging for something, often looked stressed out, and didn't entertain himself well. Now, he plays with toys, explores new areas of the house "on his own" (we watch him if it's an area we might step on him or there's something dangerous, although honestly he spends a lot of time hiding in our junk in the closet. He loves scream/laughing and wood-bopping for hours into the nooks and crannies), and is allowed to fly onto whoever he wants whenever. He's the most easy-going, well-adjusted parrot I've ever met and that all happened when the wings were allowed to grow out.