Growing up I had German Shepard Dogs. They are great. Loyal, protective, great with kids. My mother tells me our GSD used to lay in front of the stairs and push me away when I was a baby crawling around. However, they shed. A lot. Clumps of hair.
When I was older we had a Doberman. Also a great dog. Loyal, protective, loved to play. As a matter of fact, I told my dh that if my dog did not like him when he came to pick me up we would not be going on our date.
We now have a pitbull mix. He is wonderful. Gentle, great with the kids (they snuggle him all day), protective, loyal, he just wants to play all day.
As you can see, I am partial to larger breeds. I find they make great pets. My Doberman and our current dog were both rescues ( a couple of years old when I got them). I will take a rescue dog rated "No concern" any day. They are already housebroken and are usually somewhat trained. You normally just need to teach them the rules of your household and they catch on pretty quick.