If this were subscription-based MMO there would be another beta weekend. Given that it's free-to-play, they will likely release in several weeks. It is certainly acceptable (and palatable) to release a slightly flawed but enjoyable free-to-play MMO.
Starting with two seems fair for a free-to-play game, especially considering all content is open to free-ites. I did the guardian pack but really expect to play two characters at most but this will give me the freedom to try a class I would normally not play.