I just moved my chickens to a really secured shed but their isn't really any light to speak of. I've had two young chicks die this week. I think in the dark they were trampled by the older ones. I moved my little ones to a small chicken tractor. I don't really feel that they are really secure from predators in it though. I knew it was only a matter of before a predator got in the coop though. I plan on making bigger, more secure coups. I'm going to keep free ranging the guys but putting the gals in a tractor. I know what it's like to lose so many. Once my flock went from over 60 to less than 20 birds due to a couple of stray dogs.
If your shed is more secure, could you put some windows in it? And once you do that maybe divide off an area for the young chicks so that they're not getting trampled or bullied?