In the lore of Dragons within the realm of Azeroth every Dragon has a Visage Day. This helps them identify what they want to be seen as, in some cases lets them express their personalities better.
Dracthyr should have this day. And here is how i would do it.
DRACTHYR QUEST
In the hairdressers in Valdrakken there is a little whelpling talking about his visage day (its actually in game right now) and how they dont know what they want their visage to be.
The quest line should involve helping the little whelpling decide aswell as a whole bunch of other whelps from the daycare deciding.
Your task is to gather all the Races of Azeroth and a bunch of whelps, nether whelps, ruby, proto (under Vyranoths assistance and guidance ofcourse). Basically everything. You line them all up at a special area (id say the best place to do it is somewhere memorable to dragon kind, Dragonblight could be one spot but id say seat of the aspects would be the logical place (could be a new room only dracthyr can access for this quest).
Then one by 1 all of the whelps pick their races and give a brief reason why. Then at the end Alexstraza turns to you and asks you to pick as you are no longer forced under the guize of Neltharion and are your own free dragon now.
Once you pick the race, it unlocks ALL the races in the barber. Each race starts off as a basic race and over time they could add 3-4 dragonfied options per race if not more.
Once you have completed this quest you gain a new Visage Passive which lets you stay IN visage form in combat and only coming out into dracthyr form to use your abilities like Fire Breath, Deep Breath, Dream Flight, Eons. basically anything that currently turns you into a dracthyr from visage form atm any way.
This would be countered by the passive “chosen Identity” if you dont chose to swap to dracthyr form in combat, you dont, but if you do you swap like a worgen.
WORGEN QUEST
Now that Gilnaes is Liberated the worgen druids have established a grove of sanctuary that worgens can drink from to reduce their rage.
You help the Worgens gather moonwell water from across azeroth and use the scthye of elune to create a Place of sactuary for the Worgen people.
Once the Worgen gather quest and related cinematic is done, Worgen can now toggle on or off by drinking from the well if they wish to appear as a human or Worgen form in combat.
Picking the Human form nets you a special interaction with your own personal Cooldowns. Using a cooldown for your class will enrage you turning you into a worgen for the duration (cosmetic only) and swapping you back to human afterwards.
Doing it this way will not only let you keep your Worgen customization but let you do the most important thing in the game, Transmog.
If you added this to the game as a level 1 option (once you leave starting zones respectively) you would see a whole lot more people interested in playing evokers or Worgens.
Id say you should have a majority of races ready to go for Dracthyr but if that is to much just give us like 4-5 and add more over time.
Tauren - (include Highmountian and Taunka)
Zandalari Troll - (Sand and blood Troll skins)
Vulpera - Just Vulpera cos Adorable
Darkspear - (Forest Troll skin aswell)
Kul’turian - (include skinny males)
Human - (Not use Female)
Dark Iron and Wildhammer Dwarf (for those themed RPrs)
Gnome (just gnome, not mechagnome)
And then if they are using any of these respective races, instead of giving Dracthyr their own Racial armor, give them the option to wear any of the races they are currently appearing as Heritage armor. Gnome gets gnome, vulpera gets vulpera, Tauren gets Tauren, HighMountian gets high mountian, Taunka gets screwed (maybe give them new armor based off their theme, could also be later cos of Icecrown revamp coming).