When dragons first introduced to the warcraft setting, they seemed to be fairly standard. Large, powerful beasts from the Northlands, flew and breathed fire, and were intelligent. Thanks to their reclusive nature, they were an easy fit into the greater world.
And then Day of the Dragon came, and everything changed. Dragons were now divided into five flights: Red, Black, Green, Blue and Bronze. The Black and Blue flights were stated to be extinct, and Bronze and Green didn't appear to be in a particularly good state either. Rather than a single dragon queen, each flight now had its own aspect. However, the most important change was that dragons got a ton of new powers. Dragons were now a race of shapeshifters, assuming human or elven forms to wander around society unseen. Dragons were as capable of using magic as mortals, and possessed many ancient secrets that made their arts surpass those of the other races. In addition, each flight had a particular focus, with special powers in that sphere of influence. Getting the dragons to fit into the greater world became quite a bit more difficult like this.
WoW made that task nigh-on impossible though. Firstly, it restored the non-red dragonflights to a functional state, with even the blues being capable of fielding large numbers. Secondly, it showed that the dragons had absolutely zero problems working with the mortal races (or, in the case of the blacks, manipulating them for their own goals). Thirdly, it interpreted the powers from Day of the Dragon as broadly as possible, revealing that even the youngest whelps possessed shape-shifting and intelligence en par with a human. Fourthly, it gave the dragons a duty to guard the world. Finally, it also introduced the dragonkin as servants of the dragonflights (they were also in Warcraft III, but their place in the setting was unclear).
At this point, reconciling the dragons with the rest of the warcraft universe became quite difficult. Let's count a few ways off the top of my head
1. If the black dragonflight is entirely willing to infiltrate mortal societies to manipulate them, and has a ton of shapeshifters at its disposal, where are all the historical infiltration attempts? Human, dwarven and elven society don't seem like they were run by a cabal of shape-shifting dragons, and yet black dragons don't seem to have had much of a reason to not at least try and take over. The other dragonflights could have tried to stop them, sure, but there seems little evidence of such a shadow war either (?And that was the seventy-third time one of the princes of Stromgarde lost a new fiance to a sudden raid by red dragons.?)
2. If dragons were so much more than just flying leviathans of destruction, why didn't that come up during the red dragonflight's subjugation by the dragonmaw clan? Where's the army of shape-shifting dragon whelps?
3. Where were the dragonkin during the second war? Despite Alexstrasza's years-long captivity at the hands of the dragonmaw clan, there seems to have been no sign of her army soldiers showing up to do anything about it. Likewise, Deathwing seems to have been short his own army of dragon soldiers as well.
4. The bronze dragonflight's duty of guarding time is a bit out of place in a setting with a seeming lack of time travel outside the bronze dragonflight. The most anyone else seems capable of doing is some very rudimentary 'haste' and 'slow' spells, and no one seems to give much of a fig about that.
So, let's talk about ways to get them to work in the warcraft setting, as well as some other fun ideas.
Restricting dragon shape-shifting
I think this one's the most important, because having all these hundreds, if not thousands of shapeshifters running around doesn't really work all that well in warcraft history. I think an old age requirement for the more advanced dragon powers (possibly even intelligence) works well. Not only does that mean that only a few dozen dragons have shape-shifting, it also means that the ones who do are the most devastating to lose and difficult to replace.
Dragonkin as lair guards
Since dragons constantly getting to and leaving their lairs is bound to attract attention (which isn't a good thing, due to dragon-hunting seeming to have been a thing in-universe), the dragons instead leave the guarding of their nests to small groups of dragonkin. Like in the old RPG days, these could be transformed mortal members of dragon cults, giving their service to the dragonflight in return for powers, or some sort of boon (imagine a small village where no one ever gets sick, but their three strongest youngsters join the dragonkin every ten years). For the black dragonflight, this could possibly be a forced process, though I think a 'deal with the devil' kind of thing could also be interesting.
Because of their function as lair guards, dragonkin would only exist in small clumps, not easily turned into an army.
Dragon Infiltrators causing Dragon Hunts
The black dragonflight is severely outnumbered by its enemies. Why not let the mortals help with that?
?The book 'A 103 magical uses for dragon corpses' was first published in the year 112. It was the only book to be published by reclusive magical scholar Ardent Ebonheart, describing magical uses for the scales, blood, bones and organs of red, blue, bronze and green dragons. Oddly absent from his novel were uses for the bodies of black dragons, which he dismissed as 'Mountains of waste material'. Later research performed by Oridian the Verdant disputes this conclusion, dedicating an entire book to Black Dragon reagents.?
Bronze Dragonflight: Guardians of the fundamental forces
While time magic is barely used in the warcraft setting, we do know that magical research in general is a major factor in the setting. So, what if the bronze dragonflight wasn't just there to guard time, but all fundamentals of the way the universe works? While the blue dragonflight would be there to police the breadth of magic, the bronze dragonflight would be guarding its depth, making sure no one accidentally unravels the concept of Azeroth.
Bronze Dragonflight: Keepers of time
As an alternative to the above, you could also have the bronze dragonflight as still being concerned with time, but as its keepers rather than its guardians. Their goal is the recording of history, making sure the titans receive an account of Azeroth's fall in the case the worst thing happens. This has some basis in current canon, with Nozdormu apparently keeping his own collection of trinkets throughout history.
How do dragons work in your setting? Do you have any neat general ideas for dragons? What other issues do you have with dragons?