Not only that but it would be time consuming for artists and designers to make those races playable. And I think Larian has plenty of other areas of development in which asset assignments are more dire than this.
To make ALL of those races? Of course! But to make at least dragonborn and warforged available, plus one or two others? I would say they will be missing a big opportunity if they don't.
Furthermore, as I said, with each DLC or expansion they could ad another race and class, and that would keep them in business for years...
P.S.: I say warforged and dragonborn because I think those are pretty much almost mandatory. Just hope they don't fall for the "there can be no warforged in Faerun"...
