Know Your Lore: Of Elune, naaru and night elves
Quelling objection
But let's look at the main objection to the naaru theory -- the thought that making her a naaru homogenizes night elf culture. That's something that simply isn't true. As it has been pointed out, the night elves are not interested in pursuing whatever crazy theories Velen happens to have. Their culture is steeped in thousands of years of beliefs, and one draenei pointing out that their deity isn't really a deity isn't about to sway those beliefs.
Regardless of whether or not Elune is a naaru, it will not change anything that has happened before. It will not change whatever miraculous acts she may have performed over the course of history, and it will not change how the kaldorei view their goddess. To the kaldorei, Elune is simply Elune, beloved and treasured. If Elune turns out to be a naaru, that is not going to change their beliefs or their devotion one whit.
We know nothing of the naaru. For all we know, they could be gods of a sort -- gods on a level that we cannot fathom. They are not any less extraordinary simply because they speak and make themselves known to the draenei and others. They appeared from nowhere and proceeded to save an entire chunk of draenei civilization out of benevolence and kindness, with no real reason to do so.
We don't know the extent of their wow gold powers, but we do know that the death of a naaru is a very rare thing indeed. They can be killed, but it takes unusual circumstances to do so. They are as immortal as the draenei themselves -- they age, but they rarely ever die. They can be killed, but it is highly unlikely you'll ever see that come to pass. The fact that two naaru died over the course of Burning Crusade was an anomaly, one that was pointed out in the first Ask a CDev.
That said, there is something to be said about keeping massive stories tidy.
Loose ends
WoW is a massive story that spans thousands of years, has countless defined characters all with their own stories, has countless races with their own histories and cultures, and has a timeline that is slightly more convoluted than Nozdormu's everyday thought patterns. Think of it as a giant tapestry that is continually being woven, and it won't end until the final day when there are no more expansions and there is no more story to tell.
But within that tapestry there are patterns and connecting diablo 3 gold threads ... and then there are the loose threads that stick out. Threads like what exactly happened to Gallywix and why he hasn't been removed. Or what happened to Koltira. Or why the humans worship the Light as a belief, but don't really have a deity to speak of. Or why the Titans left the world behind and haven't shown an ounce of interest in it since.
Or why, in this mangled, beautiful mess of a universe, there is exactly one society that has a singular god, and why that god has chosen to ignore every other race on the planet in favor of one of its own creation.
These little threads here and there may be interesting, but they are also distracting from the main story. Eventually, these threads have to be woven back into that story, or we're just going to end up with a jumbled mess of events that makes no rational sense. We're going to end up with a lot of loose ends and no real resolution to any of them. While WoW is not a story in a traditional published book sense, it's still a story -- and it needs to be treated as such to keep it a cohesive and enjoyable game, from a lore standpoint.
Blizzard's development team is well aware of this. They're reminded of it every time they have an Ask Creative Development thread. They're reminded at every lore panel, on the forums, on Twitter. They can't help but be aware of it. What we as players have to realize is that while we love that story the writers have given us, they love it just as much, if not more so than we do. And they aren't about to ruin something so many people treasure.