I'm going to appologize in advance for..
My good sir, you are so out of the whole picture it's not even funny. Lore-wise, you have little to none idea of what has actually transpired over the expansions and before WoW as far as the storyline goes.
On the "return of the lich king and pew pew and omg and huge dark lords and harry potters" i get the impression that you are an 11 year old taking game content, getting it out of context and putting it back with a "return of" title in front. It's neither logical nor fun (though blizzard has been known to make exceptions to fun, just for shits n giggles, since there is no other explanation why kael'thas needed to come back (for real i mean), or why one of the 4 horsemen is still like.. in 3 different places at the same time in the game, or other great game inconsistencies, etc.
Thirdly... well, you don't even know the name of the supposed "main evil" of the lore (i would have gone for the typo but u wrote the same name all over the place so it's obviously not the case).
Other than that, great post ))) lel