>>50832166I would totally revamp movesets, typings, the type resistance chart, cut down the number of types and balance Pokemon out more. I would allow for more than four moves in the main game, but you can play classic 4-move mode against other players or like in a special battle facility. Even though I'd prefer to lessen the number of types, adding more is also fine. I just want things shaken up.
The story should be more exciting, with crazy setpieces and unique Pokemon bosses. Every badge should have its own little arc, nothing too intrusive or wordy, but always something memorable and strange.
Battles should be much faster and use fewer unnecessary reminders, things like weather that can be represented visually. As many other enemy Pokemon are on the field, you should be able to use that many mons too. Except for crazy boss fights where you can use several against one or two powerful Pokemon.
Most importantly, I want a serious tournament that's part of the story. A series of knockout matches, with a midgame qualifier and then a grand finale. And there would be a decent number of trainers who would apply, and you could fight a different lineup each playthrough, whether its random or maybe you get to affect who ends up winning and going against you. Maybe you can pick your rival from one of 16 characters, to have a sort of special character to drive you forward.
Winning the tournament only grants you access to the Elite Four training grounds, where the Elite Four each have their own gym, which you must beat to fight their stronger teams in succession, and then against the ultimate champion.
The villains would have a really dense organization too. A lot of battling, and a lot of variety of teams.
Aside from maybe the first few gyms, strong trainers like gym leaders and villains will generally not be themed by type. They will use a challenging variety of Pokemon and be themed more around strategy or aesthetics/personality.