Chicken wire isn't safe at all.The chicken tractor is pretty safe we believe - wrapped in chicken wire. Our ground is very hard - lots of rock so little chance of anything digging under. Our beagles often will warn us too if they sense anything outside. Understand about the light - just an added deterrent. I worry most about the racoons and cats and think though they would have to work hard at getting in and likely our dogs would sound off alarm. We are converting an existing 4 1/2 x 6 1/2 shed to coop and will have 8' tall run around it. Probably can get it done in a couple days once we start.
Small chicken killers can fit right through chicken wire.
For your coop...make sure you use 1/2" inch hardware cloth instead of chicken wire. It's easier to build it predator proof from the start then have to try to make it predator proof afterwards.