I have serious asthma and allergy problems too. Singulair works for me. I also use a netti pot every single night. I built my coop as just a framed box with chicken wire sides and perches for them to sit on. I made it with an open bottom so that I can just move it to a different spot when it needs cleaning. As an added reward, when I move the coop, I have a really great spot for a garden. I would put the hens in at night and let the roosters get thinned out by the raccoons--Just kidding.
Your husband is right about them being good to eat the bugs, but he needs to take responsibility for them. My husband gets angry too about the things that we can't do because of my asthma. Its frustrating for him. Your husband is not an autonomy, when he makes a choice, he needs to take the whole families feelings into consideration. He sounds like a very selfish and irresponsible person. An overgrown beak is a serious problem which can cause a chicken to starve to death. That becomes a neglect issue which he can be prosecuted for.
If you want me to, I'll call the Humane Society and give them his name, maybe they could get him to take responsibility-- again, kidding. But seriously, if he wants the chickens, he should at least help you hold them while you doctor them.