More suggestions / ideas:
Add explanations in the Pokédex on how to unlock entries, including height and weight for Pokémon
Show every location where the legendary dogs can be found
Add a place where the dogs are more likely to spawn for shiny farming 😉 (for example, Burned Tower B1F since it’s the first place you find them), or make them more likely to appear on certain routes for about an hour
Automatic prestige for Pokémon, then move them to the bottom of the team
Add more Mega Pokémon (Dragonite, Raichu X and Y, etc.)
Implement the special split
Add more items to the game
Add more mini-games to play while waiting to catch a Pokémon
Maybe reward a Master Ball for completing a region’s Pokédex
Add some Easter eggs with rewards, like 10 Ultra Balls, a stone, or a basic/ez to get shiny