GH: Why didn't they just bring Gia back?

First, I must say that I' am bias because Gia is one of my all time favorite character on GH especially when Marisa Ramirez (the original) played her. But I was thinking why didn't they bring Gia back to replace Alexis as an acting DA since the last time we saw the character she went off and got her law degree. Wouldn't it have been better if they got a character we're already familiar with and knew than introduce the character they have now as acting DA? I don't know what is your thoughts and opinions?