Regarding letting young chicks loose to romp and fearing not being able to get them back when you need to, it's no problem at all if you voice train them to come to you first.
It's so easy to do. Around two weeks, chicks are willing to begin to try new things to eat. Make sure, though, they have access to grit before you give them anything beyond their chick-grower. I find that earth worms are almost always a big hit. When presenting treats of any kind, do so while calling the chicks. I use "Babies!" You can use any word you wish or a clicker or a whistle - any signal that the chicks will directly associate with getting something wonderful to eat.
This training is usually accomplished in mere days, and it lasts for a long, long time. I used worms, and the chicks quickly took to them. Now that they're almost ten weeks old, all I need to do to get them all to run to me immediately is to holler, "Babies!" And there they all are, front and center!
This has proved invaluable when I need them to come out from under the coop where they love to hang out and it's impossible to fish them out, or for any reason. I've faced trying to catch unwilling chicks in the past before I wised up, and it was impossible short of, what has been suggested, throwing a net over them. If it's friendly, trusting chickens you want, I advise voice training them to come as opposed to the net.
