Not much of a common trope eh?
I'm talking about the classes, not the NPCs. Frost Mages don't use Necromancy, Frost DKs do. That's a fundamental difference between the Mage and DK classes.The moment you start talking about what NPCs start doing or stop doing, you're no longer talking classes, since NPCs do not have "classes".
Your Necromancer concept isn't very popular.To say my necromancer spec is 1:1 with death knights is blatant trolling at this point. Not to mention you're, again, moving goalposts. A new class with a blood healing spec would change in nothing the blood tank spec of the death knight.
You must not be reading a lot of the posts in this thread. Many people mentioning Bards are wondering what their place is exactly in WoW, and what exactly they would do.And you've repeatedly failed to prove that this is a requirement. Otherwise, I can create arbitrary rules too. For example, "you tinker lacks something very majorly important to become a playable class: a playable Warcraft 3 campaign hero. After all, all three expansion classes so far came from playable WC3 campaign heroes. You never played a tinker in the official campaigns."
And you cannot disprove this arbitrary rule of mine because it's based on facts, too.
There's a reason for that.