First of all I want to congratulate Larian not only for this particular game but for all of their work through the entire Divinity saga. I started with Divinity II, it had an incredible localization to Spanish and I know it didn't sell well enough and thus the next games only had texts or, as with this one, nothing at the moment. And I also understand that it's not the number of speakers available but the number that are actually potential buyers. I believe that right now the Hispanic community could become a good market for you, since the release of the original Original Sin the name of Larian and Divinity has become more popular and, at least at the forums I usually visit, there are tons of people who are eager to taste this great game but can't because their English is not good enough for this game.
And then there is people like me who despite of understanding the language, pronlably not to fully understand the game, prefer to enjoy it on our mature language. So please Larian add more translations to the game not only for us but also for the Italian, Chinese, Japanese or Portuguese/Brazilian people because I want this game to be enjoyed by the larger amount of people possible as I'm sure you will.
Greetings.