Having read and liked both, I claim that Luminosity is not an improvement on the original, it's just a different story, if based on the same premises. Like the Twilight series, it has its up and down moments, though unlike Twilight, it generally gets better written as it unfolds. Presumably because you didn't have an editor to make you go back and rewrite marginal parts into something publishable.

Nah, who am I kidding, the original is better written, it has far less of dull narrative.

Well, I suspect that if you were to ask a Twilight forum, you'd get plenty of people claiming that (many without reading Luminosity). It's not clear to me what follows from those claims, though, if anything.