An interview was done with Taiwanese Business Weekly, which contains some info about the long-term future of the game, provided by John Hanke, “the father of treasure dream Go,” and CEO of Niantic.
All in all, Niantic will be relying on new Pokemon generations as a yearly release. New gameplay systems or improvements will happen in a completely different timeline.
In the interview, John said that the next update will contain Gen 3, and will come soon. He stated that there are many Pokemon that haven’t been launched, and hopes that the players can see them soon.
Niantic is also planning a new battle mode, which will come in 2018. Also, more advanced social features will come to the game. Hanke said that these features will enhance the local communities and their interaction.
So, it looks like Gen 3 will be here soon. Trainers are extremely cautious of which Pokemon to use the Stardust on because they might be replaced by the newer ones, and I have made a list, thanks to Gamepress, what Pokemon to power up and why. You are safe now!