Inga makes me think of blonde comedy maids with braids - like
Helga, it's one of those names Scandinavian characters are called in old films, but never in real life. If I throw that out of the window though, I rather like it; simple and short, pleasant sound, decent historical cred.
Morgana is a bit frilly for me, but it's not bad. I like
Mor as a name element.
Reagan is nmsaaaaaa.
Regan does have Shakespeare on its side, but it still sounds too much like a surname.