Since your breed of sheep is rarer than most, you might have trouble finding a very young ram lamb to raise up. Yes they all can be aggressive, but much of it is in the raising.
@Mike CHS has more experience with commercial sheep and is a good one to guide you. Our Dall sheep are raised semi-wild, as the rams are sold to hunting preserves. BUT, they still do not bother or get aggressive with us humans. They don't tear up fences or buildings either. They do tend to do more "ramming" of each other. We do not tolerate any of the males as breeders if they are aggressive towards people. But we are raising a completely different type of sheep for totally different reasons than you are.
I am sorry that I wasn't a little more blunt in my post when I tried to warn you about the possibility of him getting aggressive with your wife or especially your kids. Sometimes I tend to be not so diplomatic, so I was really trying to not come across too hard. I am really thankful that your wife was not badly hurt although the bruising will be felt for awhile.
I think it is rather neat that you have dairy sheep. I only asked about the goats since they are more often used for dairy. I am not a big goat fan either, hence my lifelong love of cattle, and having dairy and beef cattle.
I still suggest that you contact your county extension office to see if they have any programs or seminars for the "small acreage" farmer like you. There are many more people looking to become more self sufficient on small farms than you realize, and there are alot that are "beginners" like you. Everyone makes mistakes, the thing is to listen to people with more experience and try to learn before it becomes an expensive repeat mistake, or one where someone gets hurt. Really hope we can help you on here.