Can you separate the mother and chicks for even a week? The chicks are probably at risk from the other birds when they're tiny, but after a few days they'd probably be okay. I put my broody hen in a separate shed and she hatched out the chicks herself. I kept them shut in the shed for about a week then I let them out to see how they'd get on. The mother marched them straight back to the big coop with all the other birds and at night she took them into one of the nesting boxes with her. They were about five weeks old when she first abandoned them at night and they finally made it up onto the roost with her the next night.
I put smaller feeders and waterers in the shed right beside the nest, then I moved them inside the coop when they went back there. It's awkward though, as the big birds all love to steal the chick crumbs and leave the chicks with nothing. I looked in a few times to see the adults all crouched down on the floor stuffing back the crumbles and the tiny chicks perched on the rim of the big feeder a foot off the ground chomping down on layers pellets. Gaaaahhh! Now when I let them out to free range in the mornings I let the chicks out first and feed them separately, that way i know they're getting at least one big feed of the proper growers pellets each day...
So anyway, it's a little bit of work at first and you do need to keep an eye on them, but if you can work out how to give your chicks a more suitable nest and smaller feeders and waterers, in the long run it's a LOT less work than keeping the chicks separate and doing it all yourself.
Oh, and I run a mixed flock of about 30 hens and two roos, and apart from the odd 'Move it, tiny!' kind of peck, there's been no picking on or bullying of the chicks. But the mother has been very attentive and has done a great job of keeping them close to her and keeping them safe. I suppose a lot depends on what kind of mother your hen is going to be.
