that cage size is good for his age. a little bigger than recommended, but being that chameleons grow faster than most reptiles, he will be just fine. glass can be suitable, but it's deff more maintenance, as it doesn't provide as much airflow as an all-screen cage. it's your call really on what you want to do - it just all depends on how much you want to be wiping off glass walls of a cage when they start to get all yucky - and how much you might be worried about stagnant air. too much humidity or stale air in his cage might cause him to get an upper respiratory infection. not good. that's why screen cages are recommended. as for the brands if you really wanting to get a screen cage - Zoo Med, Exo Terra, LLL Reptile, Dragon Strand.... there are lots of brands out there. but a screen cage is just that - a screen cage. nothing really fancy. so buying a relatively cheap one will suffice as long as it's not TOO CHEAP, you know?
as for the plants.... the Hoya exotica (Hoya carnosa 'exotica') is good, that is known as a "Wax Plant" . as for the other one, Stephanotis floribunda, I'm not sure. I haven't heard of that one before. Google it and see if you can find the answer? or maybe another one of the members here can provide input on that one....?
here is a great link with lots of good plants that are safe to use in a chameleon enclosure. I reference this link to anyone wondering about plants
http://www.tikitikireptiles.com/pages.php?id=8
how is your watering going to work? with the live plants, that will hold water droplets really well after a good mist session - so that's good. although some will, chameleons don't typically drink out of standing water dishes (and those can be breeding grounds for all sorts of bacteria anyways), so you will need a way to provide his water to him.... do you have a water dripper you could use for his water along with misting him, or is misting him a few times a day going to be the only chance he has to drink? if that's the case, make sure the misting sessions are a few minutes long at least to stimulate him to drink. you definitely want to make sure he drinks at LEAST a few times a day. I personally have a dripper dripping at all times when my cham's lights are on, dripping onto a few plants every 15-20 seconds - and I turn off the dripper valve at night. I also hand mist with a pressure mister 2-3 times a day to add humidity. these two methods combined, gives him water available to drink, whenever he wants. that's just my preference. you definitely don't want him to dehydrate. I also have an automatic mister, set on a timer, that I use when I am not home for long periods during the day and can't be home to manually hand mist. just don't OVERDO it either and soak his cage too much.... TOO MUCH humidity can also give him a respiratory infection over time. give the cage time to dry out a bit between misting sessions, and make sure to check his stool samples - his droppings are one of the quickest ways to tell a few things about his health. his poop should be brown, with white urate on the end of it. a pretty good white at the end of the brown means he is getting enough water. if the urate is yellowish, he is not getting enough water. and if it is orange, then he is probably dehydrated and you need to act quickly to save him. a lot of hydration also comes from the food you give the chameleon, so make sure you have a variety of insects to feed him. the more safe feeders you got, the better. and make sure you properly gutload them as well.
with your prior experience with reptiles, I'm sure you will be a successful chameleon owner.