Nope, Popplio is just trash, this generation we're playing with FIREH. Look at the best (for the Story) starter for each generation:
Gen 1 Bulbasaur
Gen 2 Thyplosion
Gen 3 Swampert
Gen 4 Infernape
Gen 5 Serperior
Gen 6 Greninja
We're about to start another Starter Cycle and given that Greninja was the last one the next one will be either Rowlet or Litten and I'm betting on the Tiger...