Evolve Pokemons
We can't have a Pokemon game without some sort of evolution included and in this case, a few of our furry good friends can evolve and get back at much better in the long run. As you can imagine, progressing your Pokemon is quite costly and you will not have the ability to evolve them all (or a minimum of not anytime quickly). Rather, concentrate on the ones that you use the most frequently in battle and have the higher variety of stars.