Just like any other game. Boring and easy storyline. And I'd see what to implement (like Wi-Fi, Contests, Battle Tower, etc) to make it better. Just to follow the tradition.
Otherwise, if I wanted to make a revolutionary game, it would be an MMORPG. You could visit any or all the regions known up to now. But, first of all, there are lots of things I'd do to make it better. Normally, you catch six Pokémon and level them up until you beat everyone without caring about IVs or natures. I'd do something about IVs. I can't erase them, but maybe there'd be a way to increase them until they all reach 31 IVs in everything (and it becomes a fair game). I don't know what I'd do about natures, but you'd have some way to check it before catching Pokémon so that you don't have to have a bad team before access to a daycare. And to make training easier, it should be much quicker to level up and you'll always know your EVs. There'd be ways to reduce the ones you don't want aside from berries. Also, egg moves would be able to be move tutor'd. All this to avoid extensive breeding and let you play with your wild Pokémon as a competitive matter. Otherwise, you'd just pass the game normally and then start to breed for a competitive team.