I like Ophelia and Octavia the best, slightly prefer Ophelia.
Catherine Ophelia means "pure help" which I think is very nice.
I voted for Octavia, but Aurelia is a close second. Although I like the sound of Ophelia, I really struggle with this name. She was a character in a Shakespearean tragedy , and she ended up committing suicide (drowning herself to death). That's a highly negative connotation for me...
Catherine Octavia is striking. Octavia is one of my personal favorites. It's feminine, strong, elegant, luscious, and ornate without being frilly or unwieldy. I also like Catherine Aurelia.
Catherine Aurelia gets my vote.
I like Ottoline better than Ottilia. Catherine Ottoline is pretty.
I know a Catherine Avalon.
If you want an O name, you can spell Aurelia with an O. I know an Odette Orelie. She put the e with the accent in it cuz she didn't like the oral part of Oralie. Hey - What about Catherine Odette?
btw I like your style
Classic first name with an offbeat middle
William Balthazar is really handsome!