I have been doing very much the same handling-wise with Yuki since I got her. Today was the first day she's ever willingly climbed onto my hand without huffing and puffing.
Since we got her in February (Or the end of January, I forgot which), I take her out on a daily basis and set her on a large ficus tree we have in the house. Sometimes I would do it 2-3 times a day, usually on the weekend. I would then treat her to some living prey on the tree, which she would hunt. (Crickets, worms, whatever sticks!) At first she was a beast, always hissing, trying to bite, the works really. When she was extra angry, I'd put her over my head and carry her over to the tree, same as always. She'd scramble down onto that tree quicker than I could blink!
I'll have to see how she is tomorrow, or later today. Just reward your cham each time you take him out so he learns that you holding him has its advantages

He'll come around, you just have to be patient. Some take longer than others, some are just used to handling from their birth.
As for him not eating out of your hand anymore, keep trying. He'll come around again. Yuki is great with that now, she'll even snap things that aren't moving from my hands now! (Apple slices and what not, she loves them, now that she's tried them! Used to puff up and sway, smacking her head against them before...) Try holding prey at their outermost parts to give him as much surface area as possible. (Holding crickets by the leg, for example) If he doesn't eat it and turns away, gently put it on his branch, always holding the leg/whatever you were holding. If he STILL doesn't want it, let it go and slowly move your hand away. That's what I did with Yuki, and it seemed to work for me.
::EDIT::
I should also note that the first couple of weeks, she'd have no problems coming out, eating from my hand, etc. But then one day, she just stopped, puffed up, hissed and tried to bite me. She wasn't even shedding. I thought that she suddenly decided to hate me, and she'd never go back to how she was. Slowly and surely she's going back though, and I hope yours will too!

(Although I hope that he changes faster than she did for me.)