It's decent, but
Christiana is close enough to
Christina and
Briana that it doesn't seem all that refreshing even though it's not a very common name.
Christina and -iana names, such as
Briana, are past their heyday and seem dated. I'm sure that
Christina will be ready for revival eventually, but there were so many Christinas born in the 1970's and 1980's. I've known a bunch of Christinas, so it still strikes me as overused.