You said..."he actually seems to like being handled. I was in the cage this morning putting in a bowel of mealworms for him. He actually came over to my hand and crawled onto it and sat there while i was working"...when a chameleon comes out of the cage voluntarily its not necessarily that he likes being handled...its more likely IMHO that he wants to be out of the cage or views you as a place to perch or a way to get to something higher. It is not aggressive behavior to just come out of the cage onto you. You will definitely know when he is being aggressive...he will do any or all of the following...flatten his body vertically, hold one hand up close to his body, coil and uncoil his tail, brighten his colors, expand his gular pouch, gape, hiss, lunge at you.
You asked..."is this normal for a docile chameleon, or is this behavior typical of a problem i dont know about?"...there are some veileds that are "docile" by nature and there are some that are aggressive towards the keeper in a way that is idicative of protecting its terrritory. Just like people's personalities differ, so do chameleons'. Although its not IMHO good to handle chameleons a lot, I have never seen it to cause any problems to handle it once in a while IF the chameleon is willing.
You said..."i am not using a drip system, i am just going to mist morning and night. SHould i mist all the plants and just be careful not to mist charlie, or should i mist in one place and train him to go to that one spot when he is thirsty?"...hydration is important to the health of your chameleon. I use a dripper and still mist the cage. I leave the dripper in one place, positioned so that the drips fall onto the leaves of a plant. I mist near the chameleon's nose and gently spray until he is done drinking. It may take several minutes for him to start to drink and he may even be annoyed by the spray at first. Just be sure that you don't spray it in such a way that the water can be aspirated (go into his lungs). The more opportunity they have to drink, the better. Use warm water, not cold too. The dripper can be as simple as a deli cup with a tiny hole punched in the bottom of it so that it drips at the rate of 1 or 2 drips per second. Not keeping it well hydrated can lead to kidney problems.
Regarding feeding...a subadult needs only to be fed every second day. Until he reaches full adult size, as long as he isn't getting fat, there is no reason to skimp on the food. Variety is good, but go easy on the waxworms. I don't give them to the chameleons more than once a month. You can use crickets, silkworms, superworms, roaches, tomato horn worms that were NOT raised on tomato plants, etc.
Dusting the insects and UVB exposure and gutloading go hand in hand...how much and how often the D3 is given depends on the UVB exposure your chameleon gets. He needs calcium, and if raised under artificial lights, calcium/D3. Depending on the gutloading, he needs vitamins/minerals too. Be careful with the D3 and the preformed vitamin A because they can build up in the system. Vitamin A from beta carotene can't. There is a good gutload on the ADCHAM website.
Plants should be non-toxic and well washed (both sides of the leaves) since veileds eat vegetation. I cover the soil with stones that are too big for the chameleon to ingest so that they can't eat the soil and become impacted....a good reason for not using substrate too.
Veileds can be fed fresh greens (such as kale, collards, dandelion greens, mustard greens, etc.) and fruits (such as wedges of apple, pear, pieces of melon, etc.) and veggies (such as diced red pepper, squash, sweet potato, carrot, etc.) and even non-toxic flowers that come from fertilizer/pesticide-free places. They will/can eat pothos and leaves of other non-toxic plants too.
You said..."the cage itself is 30x18x30"...that size is fine but bigger is almost always better. I have kept veileds in a similar sized cage and they have lived to be over 7 years of age.
Good luck with your chameleon!
What is up with that combination...?