No matter which races end up making it in the game, I hope the choice will actually matter. Thinking back to NWN2 for example, if you played a drow you'd get exactly one (1) line of dialogue where an NPC would question why you are around. It can be an important factor for the immersion and the replayability of the game to make sure every race gets the appropriate writing attached to it.
So I believe it would probably better to go for a "less is more" approach when it comes to the number of playable races. Though I of course hope for there being proper subraces, but I wouldn't be surprised if they have to skip out on those.
