I don't get it either honestly. Nothing about it seems appealing to me. I don't think the OP is claiming that everything has to appeal to him just that he thinks it would be a waste of a playable race, to him/her.
I would tend to agree, nothing amazing about it, novelty perhaps, but nothing amazing. I don't see much amazing about many of the remaining options of races though.
Ethereals perhaps, that could be.
Furblog.. I don't think so
Gnoll ... no thanks
Jinyu .. no
Kobolds .. No take candle!.. I don't and wouldn't, ugh!
Nerubian .. how would this even work?
Quillboar .. uhhh no
Sporeling, Tuskarr, Qiraji, Naga, Murloc ... No! No! No!
Drakoid, Dragonspawn, Cenarius Favored Children, Satyr, Centaur ... talk about some fundamental game changes for any of these
Arakkoa.... never in a million..
It's just no that feasible to me and I'm not thinking any of the races we have now would be engaging to play verses what we have. Not saying we couldn't have something new, but I don't know what that would be. I like Worgen and Pandaran and to me they were new when WoW introduced them to the game. I even like playing Goblin. I just don't see the draw of any of the current races at this time.