>>32622750If you're asking how to make the game the most easy to beat, just use your starter and nothing else except HM slaves that receive no Exp in fights. Carry lots of healing items and Revives on you and use your weaker Pokémon as pivots if you need to heal.
If you're asking for the most fun team to use, just use your favorites, and if you've already played the game with your favorites than go out of your way to use Pokémon you haven't before, that way you might make some new favorites.