The sad thing in my eyes is, the whole H/G ship had about as much, if not less, development by the end of HBP than if she just threw all fucks to the wind and tossed in Myrtle.
I'm not saying I hate the H/G ship, nor am I saying that H/Hr would have been perfect, but Ginny's sudden rise from a mostly background support to sudden love interest was kind of a whiplash causing event, especially when it didn't have to be. If she'd just been built up a bit more in Order of the Phoenix, if she'd gotten a growing role that showed a greater competence and personality than just a background 'Friend's Sister' and maybe a building closeness to Harry, it could have been a whole lot better in HBP, but as it is, it seems to me about as sudden as Myrtle perving of folks (And Harry) in the Prefect's Bathroom.
We had no real indication that Harry had gotten to know Ginny all that much at all and, even without Hermione in the mix, there were probably better choices of folks that they could have hand-waved by with Harry knowing them off screen or something (Quidditch teammates and the like), but the one who stands out the most is, yes, Luna, a character Ginny had a three or four book head start on with which Ginny did all of jack with. And despite being in less than half the books and possibly in less of the material than Ginny, Luna managed a unique bond with Harry. Again, not saying it's an end all ship, but more that this shows J.K. could create such a bond in a shorter time, but it kinda seems she tried to force things 'back on track' too much and kinda forced it off the other side to where the pairing she wanted and got at the end felt kinda unnatural and forced, instead of finding a way for things to flow to her desired ending better.
That said, a sudden dead Harry/Myrtle ending would have been funny as fuck, even if completely out of nowhere.
