Hi Kira. Gigi was a hand fed baby that I brought home at 6 weeks. She turned 1 on 2/1/19. She had a step up from her cage for only a short time. Then a few times I had to chase her around the cage, so I decided that she could come out when she was ready. I open the door and she comes out. In time I also had trouble touching anything in her cage when she was in it. If I needed to clean poop off a perch she would lunge and try to bite. She was calm when I put her food into her cage. At 6 months I got her a new cage that I put food into from the outside and I think it was just in time. She is really cage aggressive. So, is he biting you when you are touching him in the cage or the stuff in his cage? Another typical thing is Linnies can be hand shy. Gigi is, she would rather I not touch her. Linnies love their people but not their hands. As far as the cage being high, I don't think that leads to aggression but I like birds at eye level so they can be part of the action. Gigi is really excited when my young grandchildren visit. She spends lots of time on the floor of the cage, getting on their level. I think it's great that you are taking him out often and rewarding him for behavior you like. Interestingly Gigi is not very food motivated and has never taken anything out of my hand.
All that said, Gigi is incredibly friendly. She is fully flighted and flies to me often, hanging out on my shoulder and lap. I can touch her with my face and sometimes my hands. But she doesn't bite often, she mostly just flies away if I'm getting too handsy. When I come to her cage when she's in it, she quickly comes to the edge to visit. So it's been interesting to figure out Linnies, she is very different than birds I've had in the past.
So it doesn't surprise me. What else does he do when he's out? Does he have any activities, places he goes? Gigi really likes her play gym. It's from 
