Wildhammer Dwarves - Around since vanilla. Wildhammer stronghold in Outland with WC2 hero Kurdran (TBC). Council of Three hammers between Wrath and Cata. The Twilight Highlands quest line in cataclysm for Alliance was literally to unite the Wildhammer Clans under the Alliance banner which would have been the perfect introduction for them as an Allied Race if Allied races had existed in Cataclysm. From what I've read they play a pretty significant role again in BfA.
There are actually a lot of similarities between Wildhammer Dwarves and Alliance High Elves in that they are long-time members of the Alliance (going back to Warcraft II), significant presence in zones/quest-lines, have major lore figures appearing both in books and in-game and are not playable in terms of game mechanics despite being high on the list of requested (sub-)races.
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Vereesa will probably undergo some fel-infusion at some point (probably against her will).
There are 6 major sources of magic listed in Chronicle (Life vs Death, Shadow vs Light and Order (arcane) vs Disorder (fel)).
Alleria is the sister of Shadow and her partner is Turalyon who is associated with Holy/Light.
Sylvanas is the sister of Death.
Since Rhonin was clearly associated with Order/Arcane thus it only makes sense for Vereesa to become the sister of Disorder.
Of course this means Sylvanas must have a secret consort of Sylvanas associated with Life/Nature ? some yet unknown Zandalari troll druid maybe
...poor Nathanos
It only makes sense that after Blizzard turned Blood-Elves into classic tolkien High Elves, that Alliance High Elves become vampiric and fel empowered (like demon hunters) so they can fight fire with fire.