I doubt that we'll be going back to faction specific races anytime soon. I could be wrong, but that's just my two cents.
The draenei people asked for was not the draenei we got. I doubt anyone expected Lawful Good Eredar.well, thats happens with belves worgens and goblins, and if i remember well people ask for draeneis too
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They compete with the Tauren as the large, brawny race. They fall into the same pitfalls as many other Horde races as being monstrous/ugly. They lack competant female options, in potential design and as an aesthetic. They fit in very well with the Horde, but fitting in isn't a reason for a race to be added. Like I explained, each race added to the game has had a design-driven reasoning behind them. Ogres don't really fill any niches other than fan service; they're about as supplementary as having Nightborne or Hozen added as playable races.
There's nothing wrong with Ogres being playable, but compared with other potential options they simply don't stand out enough. Ogres lack a unique hook for mainstream interest. They fit the mold all too well.
We need to ask "What does X race offer for the Alliance/Horde". In terms of Vrykul and Ogres, their dynamics are fairly predictable.
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Goblins are unique and fill a niche for the Horde. They might have been 'easy', but there's no other race like Goblins in the Horde. They fill in as comic relief.