One of my best friends is named Seth. He's a lot like me. He's in band (he's still in high school though~he's graduting this year). He's dorky just like me, but he's a sweetheart. He's into metal(today's metal~I'm more into the heavy metal of the 80's and early 90's though). He's a good Christian man. However, I also know a man who is a horrible person and father. But, I think you should go with Seth. I think it's still a good name, and I think he'd turn out to be a good boy. Seth William is alright.
Julia is good, but I don't like the middle name. Sorry.