He looks a little dehydrated to me, are you sure he's getting enough to drink. They won't drink from a bowl they have to see the water moving. His veil should look full and puffy especially from the back.
As far as handling him goes, from my experience aside from the rare few most Veileds are a little cantankerous. I would be careful handling him too much, they're about 90% bark however 10% of the time they will light you up. Don't under estimate their bite, don't ask me how I know. But after you let him settle down, and get used to you when you get him out of the cage try to let him be in charge, let him come to you and climb on you. They like to climb up and a lot of times he will climb on you to go up that way he isn't all ticked off at you. When you go in over top of him and pick him up he thinks you are a predator trying to hurt him. Something to try, But if you do have to coax him out do it from under him slowly, not from over top of him. You should keep the handling down to a minimum because it could cause undo stress, and shorten the life of your cham. Out of 16 years of raising veiled chameleons I had two who tolerated handling well, and that was only on occasion.
I also agree he needs more plants. I would get real ones if you don't already have them, like a panthos, or ficus, just make sure it's not poisonous to him, and wash it real good to make sure there is no pesticides on them.