As you'd hope from a Pokémon title (even if it's not quite a full-fat game), trading and training features are still a work in progress. (Niantic Labs are also looking into the Pokémon breeding inside the smartphone title.)
While discussing the game's future direction, Hanke said that he was interested in further customizing the in-game Pokéstop. At the moment you can attach a lure that ensures more Pokémon will pop up at that location -- something which benefits all players in the area. Hanke suggested that other customizations could be setup at these stops, with the Niantic Labs boss citing a monster-healing Pokémon Center as a possible new function. "That's a pretty cool idea that you can acquire an object that changes the function of a Pokéstop and give it a new ability."
There are currently no Pokémon Centers -- and no Nurse Joy -- in Pokémon Go. This needs to be remedied immediately.