Eh, I can't agree with that. Death Knights in WoW simply absorbed pretty much every ability from its fellow Undead WC3 units.
Unholy was simply a combination of Death Knight, Necromancer, Ghoul, Abomination, Crypt Lord, and Gargoyle concepts.
Frost was essentially the Lich in melee form, along with the Frost Wyrm unit.
Blood was an outgrowth of the DKs lore (Vampiric Runeblades), Ghoul's Cannibalism ability, Death Pact, and the Dreadlord's Vampiric Aura ability.
It's very easy to see how they built the DK class when you look at the totality of units in the Undead faction, and realize their goal was to bring a Necromantic class into WoW. It wasn't a departure, it was an expansion.
Here's the problem; There are no Bard heroes in WC3, TTRPG, or WoW, so you're not pulling from anything. In addition, the Bard playstyle (buffed-based Auras) were rejected by Blizzard in TBC, and we already have multiple classes using music/sound based abilities. Russell Brower (later Russell the Bard) for example was using Priest abilities in Cataclysm. Dragonsworn has been demonstrated to just be existing classes who swear allegiance to dragons. Druids and Mages for example are dragonsworn to Green, Blue, and Red dragons for example. Both classes also have Dragon abilities. Druids have Ysera's Tears, and Mages have Alexstraza's Fury.
Finally, any logical Necromancer ability can simply be absorbed by the Death Knight and Warlock classes.
I'm certainly not saying that Blizzard could never do those classes, but Blizzard tends to build up class concepts before bringing them out as classes. For example, for me to believe a Bard class is possible in WoW, I would need to see some Bard heroes fighting for the Alliance and Horde. Prominent heroes who actively participate in the lore, and are known heroes to the major lore characters. Gazlowe and Mekkatorque for example are participants in the lore, and are known comrades to characters like Thrall, Jaina, Varian, and Rexxar. There are no such characters for Bards at all, and there is no history of Bard classes or heroes in WC period. I've heard this is the case because Metzen personally despised the class and I remember a developer saying that Bards are "too soft" for WoW.
Those are Final Fantasy classes. There's no basis for any of those classes in Warcraft, and those concepts don't have enough meat to be multi-spec classes. I'll repeat that Blizzard has rejected the playstyle of Bards and Dancers wholesale, so there's really no point to them being in the game. You can give the existing classes song-based abilities (and they have).
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Wouldn't a more likely scenario be that Blizzard has no intention of ever making those concepts into classes? Instead of a Necromancer, Blizzard beefed up the Necromantic abilities in the Death Knight class. Instead of a Dark Ranger, Blizzard gave Hunters exclusive access to two Dark Ranger abilities. I also don't buy the notion that DRs weren't made available because Sylvanas was a bad guy, because DKs were based on the main antagonist of WotLK.
If Blizzard gave Hunters Pocket Factory, Rock-It turret, and a Mech form, I would say that we definitely aren't getting a Tinker class.
Again, I would remove DR and Necromancer from contention. You can place any ability for that concept in the Hunter and DK class respectively.
Dragonsworn are existing classes with draconic abilities. Mages for example have Dragon's Breath and Alexstraza's Fury, Warriors have Dragon's Roar, and Druids have Ysera's Tears. Blizzard has never demonstrated Dragonsworn to be a unique class with unique abilities. Which is why I believe that Blizzard is going to bring Undermine in alongside Dragon Isles in order to justify a Tinker class inclusion. If I'm wrong about that, feel free to mock me.
