I find this not trueI understand that feather pulling is part of his natural behavior
I have had plenty of roosters over the years, and the keepers dont damage hen feathers ever. Its aggressiveness or bad technique
Your concern for the 2 young children is well founded and no matter how you try to adjust this roosters attitude, he can never be trusted around children. He has displayed his temperament and disposition.
The egg cracking and egg eating issue.
If your nest boxes dont have deep soft bedding add some more shavings and or straw.
Making the nest boxes darker may help so they cant see or focus on those eggs may help.
Roll away nest boxes are great but not always possible for your setup.
Fake eggs or golf balls in each box help, because hens get discouraged picking at them with no result.
Gather eggs more often during the day.
Sometimes boredom and close confinement are contributing factors of egg eating and feather picking. Get them more run space and things to scratch and peck through
If you can identify the egg eater, pinless peepers for about a month may cure it.
Check the protein content of your feed and let us know what it is.