6) Destructive Environments
One of the most exciting things in the Pokémon anime series is the way the battles themselves are so energetically crafted and how powerful they make the creatures seem. Hardly a gym battle goes by without Ash and co. crashing through the scenery and leaving visible destruction along their path to glory.
To a degree, we do get to see some of this in the way certain attacks can be used to move blocking items and objects in the games’ overworld views. Add to this the occasionally meaningful weather effects or chipped background stones we see in battles, and that’s about as much interaction with the world that players and their Pokémon can have in the games.
More readily destructive environments would make the battle scenes more exciting, and could even add an extra element of chance to proceedings. Cracking earth could decrease the Speed stat of a defending Pokémon, for example, as they struggle to keep their footing on a recently wracked battleground. Attacking players would then see their windows of opportunity open wider, meaning trainers able to exploit their surroundings could find even greater battling success.