Very nice.
Catherine with spunk. Excellent.
And I spell it
Kathleen. The C spellings look weird (odd, I like most other names with C instead of a K). I don't think I've ever seen Cathline. I think that upon seeing it, I'd actually pronounce it with a line sound. And Irish spelling would be
Caitlin, with an accent mark on one of the I's (can't remember which!) I was really surprised when I saw that
Caitlin was actually supposed to be said
Kathleen.