The problem is there IS lots of lore for many of these races... in the books.
Baine and the Tauren was a major part of The Shattering in , in taking back Thunder Bluff from Magatha and her Grimtotem, partially befriending Jaina and Anduin, etc. They also had a large part in Jaina Proudmoore: Tides of War as Baine was clearly one of Garrosh's biggest dissenters and he lead the attack on the Northwatch forces in the Barrens alongside Vol'Jin and the Darkspear, outright opposed Garrosh's tactics surrounding Theramore, etc.
Lor'themar and the Blood Elves have also been getting increasingly more attention both in the Jaina Proudmoore book and in Patch 5.2. I'm sure we'll see more and more as it continues to mount.
I'm positive Baine and his Tauren, Lor'themar and his Blood Elves will be present and fighting right alongside Vol'Jin, the Darkspear, and Thrall when it comes to the final patch with overthrowing Garrosh (and likely killing his lap dogs Nazgrim and Malkorok).
Now, for me this is all great because I LOVE to read and Christie Golden is a wonderful writer (seriously love her Warcraft books). But I understand why others don't read them... though they really are missing out on some GREAT stories and lore that are simply better read in a book than seen in a game while mashing buttons. At least in my opinion
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