-Setting: The Dragon Isles (I hope you weren't expecting somewhere different). We follow Wrathion, Ebonhorn, Kalec, etc. to the Dragon Ilses, where we help rejuvenate the dragonflights. This is a building expansion: we're helping establish colonies (that we won't be managing ourselves, so not Garrisons), helping them grow, building trade routes, etc.
-You visit an Island dedicated to each of the Dragonflights, and at that Island you help restore that Dragonflight. The Aspects do not regain their immortality or full aspect power, but they regain status as an actual living species with the ability to reproduce, etc.
-The expansion eventually leads to the Void, with conflicts arising with the Twilight Dragonflight, Void Dragons, the Infinite dragonflight, etc. Other groups we might ally with, fight with, etc. etc. include the Dragonmaw Clan (who have been more or less MIA since between Pandaria and WoD), Sky Pirates, Dragon-hunting Vrykul who are trying to please Odyn by hunting Dragons to Extinction.... etc.




Mechanic #1: the Airship
The first thing you do in this expansion is commission a ship to take you to the Dragon Isles. However, you cannot approach the Dragon Isles by sea. They are massive, and their shoreline is cliffs, not safe harbors. They're surrounded by jagged rocks that make a naval approach inadvisable.
Instead you must fly to them.

Your airship is basically player housing that you can take from zone to zone, including some zones outside the dragon isles with appropriate ports. Indeed, you'll be tasked with conducting trade between different Skyports in the Dragon Isles and the rest of the world, buying low, selling high, etc. The more quests, trading, and missions you do for a particular colony, the more that colony will grow, but it does so autonomously. It's not your colony.

You will select your crew from races available to your faction as well as neutral/creep races.

Airships will be able to accomodate a variety of races and aesthetic styles including the ones we've seen in game so far as well as new designs that reflect Pandaren, Sindorei, Night Elf, Draenei, and Undead Aesthetics.

Mechanic #2. the Hatchling
When you reach end game, you will receive dragon egg from the flight of your choice. You go on a short quest-line to hatch the egg, and then you have a whelp that is your responsibility to raise. It has it's own xp bar, and each flight has it's own behaviors that may lend themselves to whatever kind of playstyle you want to play. For instance:
- Blue whelps want to learn magic, so they will copy whatever spells you cast.
- Green whelps are great with crowd control, putting enemies to sleep or making them (or you) ethereal as needed.
- Black whelps are bold and brash, and will attract attention to themselves. Best if used by tanks.
-Red whelps are natural healers.
-Bronze whelps might freeze a moment, or rewind damage, slow enemies or freeze yourself.

I have no specific thoughts on races or classes to introduce for this expansion, but there's room for such, depending on what is needed at the time.

One alternative idea to renewing the Dragonflights is rather creating new ones using Proto-Drakes, Wind-Serpents, or Elemental Drakes.

I like the idea of either making new flights, or using the serpents and proto-drakes and such to enhance/supplement the existing ones.

The whelpling idea is neat, might shuffle cc to the bronze and give green buffing and HoT but other than that, neat ideas.


Antagonists are a bit dragon heavy too, maybe have the void mutate their 'flights' to be distinct from usual dragons?

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My Worldbuilding:
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CC to Bronze and buffing/HoT to Green both sounds reasonable......

I imagine Void Dragons would be different. Maybe start having them grow extr heads (think Gidorah).

How would you expand the content, so it's not oversaturated with the "dragon" theme? Maybe touch on their supposed "cousins" like gryphons? Wyverns? Dinosaurs?

Maybe go full Kaiju. Galakrond is the Father of Dragons. I imagine Xibala was around the same time. What if there were other gigantic monsters out there in the age before dragons, and what if they started coming back?

In such a vein I have long wondered about the various gigantic skeletons around Azeroth. Like the enormous petrified "kodo" (or rather, probably kodo/thunder lizard precursor) remains in Tanaris, or the Dead Goliaths in Desolace.

Like maybe at some point in primal post-Old God Azeroth - like, say, when Freya was wandering around studying the planetwide explosion of new life - there might have been many colossal monsters who evolved from leftover elemental creatures alongside the dragons as part of the new ecosystem.

Perhaps have the existence of Wild Gods originate from certain individual animals evolving increased intelligence and strength in order to protect their respective species from being wiped out by gargantuan monsters who would otherwise hunt them to extinction.

Then such massive creatures could have largely (though not entirely; we've still got stuff like krakens and leviathans around, after all) died out between Wild Gods fighting back and the Keepers and their titan-forged slaying any that were especially laying waste to the burgeoning new balance of life around them.

Then from the same angle, it could be speculated that Draenor's Wild Gods (Anzu, Sethe and Rukhmar, especially) emerged as a similar response to Breakers and Primals marching around the continent collaterally wiping out smaller life forms left-and-right as they warred with each other for dominance.