1. An open-world Pokémon game, build around the same engine Ni-No-Kuni used, or perhaps an even better one.
2. Release the game with the first 151 Pokémon.
3. Base it in the Kanto region (Red/Blue).
4. Don't use hack'n slash - use turn based combat. It has work for the series for many years.
5. Use expansions to open the world; add new regions, moves and Pokémon
6. THE MOST IMPORTANT ONE. Capture the beauty and feel of Pokémon.