Whenever I have chicks, I'm always sure to give them outside time in the dirt with some sunshine so they can see the wide world and grow some ambitions.
I don't know about the ambitions part, but they love it!

They run around, jump on everything and freak themselves out with all the bugs and other small animals they find.
If you're interested in doing that, you should always be by their side to make sure no birds or other animals find a snack from your beloved fluff balls.
As for the roosting stick, that size is fine as the little babies will sleep on the ground together and play on the roosting sticks. (Just as everyone else has said)
A note for the future, when your chicks grow into gorgeous hens, you'll need to find sturdy sticks that are half round on the top and about 2 inches along as the hens don't like to curl their feet around the stick to sleep. Their natural stance to ensure balance is to have their feet on a slightly curved surface so that the they can comfortably roost without being knocked off my another hen when she makes slight movement.
Another thing to keep in mind is that some sticks might have splints or odd edges, so always sand down the stick that you decide on before installing it. The height of the stick can be anywhere from 1 foot off the ground to 1 meter, some people have it higher, but it's all variable to how high the ceiling is as well.
I tend to use tree branches for my chickens, they haven't complained so far!
Also, I almost forgot, pecking order is a real thing. If you want to avoid having your flock fighting over spots, have your roosting sticks all at the same height, boom, no more fighting before bed, more loving flock.
