I have considered maybe just waterproofing it, I kinda like the rustic look as well. I do have chicken wire around the top gaps, no pythons here thankfully but we do have black snakes and other smaller snakes, so far no problems with them but we will see. I will be adding hardware cloth this spring to certain areas. Apparently my girls like the vents I have found them perched at the top several times!
I wouldn't add hardware cloth to "certain areas". I would replace ALL of the chicken wire with 1/2" hardware cloth. Chicken wire has little strength against predators but does a fine job of keeping the chickens inside.