Kanto remake idea.
Expand on the cities, instead of just repeating Gen I's layout, so they have back alleys. There, you can randomly find Team Rocket grunts selling "exotic" Pokémon like Grimmsnarl and Klinklang for ludicrous prices. You have the option of actually buying the Pokémon if you grinded to have the money, to which the Pokémon will have 0 friendship. OR you battle the grunt who has disobeying over-leveled Pokémon. If you win, you have a good chance of at least one of the Pokémon wanting to join your team.
Buying the Pokémon fits in with Gen I's grimier 90s pre-international phenomenon feel. I can also see dumb ass kid Red actually thinking buying the Pokemon to be saving them, maybe that can be integrated with an introduction via a low-priced Roggenrola or something. However, making it on ongoing mechanic, even after defeating Giovanni, makes Red / Leaf a bit more of a hero that learns from their mistakes. It also integrates foreign Pokémon in a believable way, and continues to show Team Rocket as a threat via game play mechanics instead of just going through the motions in the story.
