I really like
Ekaterina a lot although it does feel too foreign for my tastes. OTOH, I adore
Katerina and came very close to using it with our Scottish surname! I loved it so much that I didn't care what people thought, lol. OTOH, there's something about the E in the front of
Ekaterina that takes the name to another level for me.
It all depends on what you're looking for in a name. If you're looking for something more exotic with good nn potential (
Katia,
Katya), then
Ekaterina might be the name for you.