By the way, they probably weren't all that valuable. I breed birds for my own use and that of my friends' -- my roosters, Domino and Wimpy at least, were probably nothing approaching purebred-ness, and their children definately aren't!
There was a fair bit of sentimental value attached. Domino and Wimpy I'd had for a while, and since I got them at about 18 weeks, and Bard was the youngest, only about 28 weeks now. I had high hopes for him. Apart from Domino, who was a little proud and standoffish, the three roosters were all quite friendly and like to be held. I've heard so many stories about nasty, mean, flighty roosters that I'm a little worried I won't be able to get such friendly boys again.
Valuable or not, purebred or not, losing a pet is hard. I think most chickens can be made to be tame if they are handled at a young age.
When I was a kid and we had an unruly rooster, my grandmother would cage him at night and the next day everyone took turns carrying him around the yard. It seemed to change their attitude as least for a little while.
I use a portable system myself, but I have no fears of any mid-size predators getting in. I use my chickens as workers in my garden and even though they are pets, they still have to work for a living.