What you are talking about is sort of a hybrid, not really a cop and not really a run, but a combination of the two. Nothing wrong with that. Many people do it that way, especially in warmer climates.
What chickens need for housing is protection from predators and protection from the elements. Those can be provided many different ways and are somewhat dependent on your conditions. Predators can get in different ways. Some predators like coyotes, foxes, or skunks can dig under the fencing. It’s not that hard for a lot of things to just push under the fence if there is a tiny gap. I saw a possum walk under a fence like that once. It sure didn’t look like there was any room but it didn’t even slow down. A common low work level way to fix that is to use an apron. Lay about 18” to 24” of wire around the outside, fix that to the bottom of your wire, and you’re done. It’s pretty common to bury that about 2”, which means take up the sod and put it back on top. That keep sit out of lawn mowers and weed eaters. If that held dogs, you may already have that.
If that will stop a bear you are doing better than 99.9% of the coops people on here have. Big dogs, big boar raccoons and such can tear most hardware cloth and a lot of welded wire. It depends on the gauge of that wire and how it is attached. Don’t let people tell you that you have to have hardware cloth. What you have is probably safer from serious predators. It’s really hard to make a large coop that size safe from absolutely everything without breaking the bank. Snakes, mice, rats, and some members of the weasel family can probably get in. That depend on the size of those holes. Snakes that can get through those holes can eat eggs and baby chicks but should not bother your adult chickens. Your chickens would love for smaller snakes to visit. They love playing keep-away with them and eventually eating the small snakes but unfortunately snakes big enough to eat eggs are safe from chickens. For rats and mice, keep that area cleaned up as best you can and don’t leave a lot of hiding places for them to raise a family. A trapping program may be beneficial, just see how bad it gets. Keeping rodents down will help keep snakes away. If you get a weasel you have a problem. It’s hard to do much with them if they show up but the good news is that they very rarely show up.
I can’t tell if that has a top on that or not. Lots of things, like bobcats, foxes, raccoons, and possums can climb that fence and get in. Obviously owls, hawks, and eagles can fly in. You might consider putting a top on that, I’d suggest something like 2” x 4” welded wire, but if you have trees, leaves could collect up there and a snow or freezing rain could cause it to come tumbling down from the weight.
Most predators are more active at night. That doesn’t mean a bobcat, fox, raccoon, or coyote won’t hunt in the day. They will. But they are more likely to be active at night and have more undisturbed time to get in. A very common strategy and one that I use is to have a predator-resistant run and a predator proof coop and lock them up at night. That pen is a lot more predator-resistant that what I have.
I’ve seen chickens sleep in trees in temperatures below zero Fahrenheit. They are not on a dead tree limb overlooking a bluff squawking defiantly in the teeth of a blizzard. That would be in a Disney movie. They were in a protected valley in a thicket and able to move around to get out of a direct wind. They do need some protection from the elements.
I’m not sure how strong those posts are. If you cover them with a solid wall, will a wind blow them over?
If you can provide a shelter for them that gets them out of a direct breeze and will protect them from predators, you should be in great shape. That pen is a huge asset. I’d certainly use it. Good luck with it. I think you are off to a great start.
