Controversial opinion maybe: Kuroko would be (is?) the most interesting character of the series if her personality wasn't constantly butchered for bad comedy. Not that the competition is especially fierce.
I can imagine... "We're almost done and... OMG!! This is like super gay!! Quick, we need to do something!!" "... Well, make them relatives or something..."
From what I've seen both her (Alina's) and Karin's magical girl sidestories humanize Alina and make her more sympathetic than what the main story does.
The Galaxy Angel anime is one of the best anime comedies ever. There's a reason it ran so long despite having nothing to do with it's original source. If you think it's "bad" you haven't watched it.