I honestly wouldn't have guessed Selene to be blonde, my guess would've been white-haired. And she is really pale.
I'm going to guess that the Vol. 9 (which'll probably come out in May or June) will show at least Lucy as a yokai with Natsu, with maybe Selene in the background as a dragon as well as the Moonlit Beauty Goddesses. This'll finally give us a clear sense about what color Lucy's scales are, since while most people have taken to drawing her with red scales, I don't think that's the case.
Like most illustrators, Ueda differentiates individual colors through shading, and (obliging by Mashima's shading policy) red is depicted a shade of dark gray (like Erza's hair). Colors like pink and yellow (the colors of Natsu and Lucy's hair) are generally the same shade, and Lucy's scales are mostly the same shade as her hair (maybe a little darker), so I'm guessing her scales would either be yellow as well, or pink.
(gods, I'm a nerd)
PS: Am I the only one who thinks Selene looks like a vampire in that drawing?