There is always some work involved in setting up and maintaining a new language at LingQ, not to mention the complaints that we get from users who find that the size of the library or the quality of dictionary for unsupported languages is not good enough. So it ends up being a distraction from our main job which is to make LingQ as good as it can be for most users.
Personally, I would like to see an unlimited number of languages, including Thai or Hindi with non-Latin scripts or even endangered or minor languages such as Canadian aboriginal languages. Hopefully, once we get a number of other things done we can focus in on that. Meanwhile we have set the bar at 1000 votes and full marks to Mike, one of our strong supporters at LingQ, for pulling it off. If you set your mind to something, it can often be done. Just like learning languages!