I liked it, and thought that it was fairly well done considering the whole thing is based on a series of fighting games. Most of the title character's friends in the show are former villains from the games.
There is really not that much else I have to say about it.
The American voice acting in the version I saw was not exceptional, but they did not butcher the lines or anything.
Oh, yeah. There is also a lot of implied lesbianism. Other than that Galixie Frauline Yuna is a proto-typical alien girlfriend comedy, the only difference is that there are nearly no male characters.
I have a friend that is beyond obsessed with Galixie Frauline Yuna. The only reason I am mentioning this is the fact that I have to have at least ten lines of text to put in a comment on the show, and I really had nothing else to say.