It looks much nicer than Geena, which looks like a bastardization of Gina, and I actually prefer this spelling to Gina. However, I find the name Gina quite boring and overused, and the same goes for the variant Gena. It would be quite refreshing if people actually named their daughter Eugenia instead, even though it's a feminine variant of Eugene, which has some type of religious background I don't like.
This is my mother's name, but it isn't short for Eugenia or anything, really. She was named after her father, Gene. Although his real name is Eugene, I would be appalled if her name was Eugenia!