Even though there are features that could be implemented, like controlled spawning, if you want special mobs to spawn naturally, you won’t find any other plugin than this, the amount of customization and ease of setting it up really makes it better than any other.
Perhaps as time goes on, this plugin may become the best in every aspect, if there’s a plugin that has a potential to do so, it’s this one.
I’ve been using resources from kangarko for a while and I can say that he’s one of the most understanding, skilled and helpful developers.