Brock goes back to his old job as gym leader in Pewter. Jessie quits team rocket and goes back to medical school, eventually becoming a pokemon doctor, moves to Pewter where she becomes Nurse Joy's boss at the pokemon center, and marries Brock, who cooks her great meals every day.
James' parents buy control of team rocket from Giovanni and put James in charge. He institutes much more caring rules for his grunts to follow when stealing pokemon, and even advocates catching wild ones instead of stealing, whenever possible. he fires Butch and Cassidy, who go on to start a rival pokemon theft organization, luring away many of team rocket's best grunts and executives, but it's still outnumbered by James' Team Rocket.
Meowth joins the political struggle to gain full equality for pokemon with human beings, becomes SNAP's most prominent spokesman (or spokesmeowth). In large part due to his efforts, new regulations are mandated by the government seriously reducing the power of the Pokemon League and changing their most insidious, clandestine practices. Overjoyed at this victory, he evolves into Persian and finally wins the girl of his dreams as well as the respect of his fellow pokemon.
Misty dumps Ash for me. I open a pokemon gym in New Bark Town and become its leader, but still make frequent journeys around Johto, Kanto, Hoenn, the Indigo Plateau, and the Orange Islands- and especially to Cerulean, where Misty is gym leader and undisputed top water pokemon master of all times, and the two of us can often be found making out on Cerulean Cape. But don't bug us!
Tracey visits us once in awhile; he travels alot after his stint as Professor Oak's assistant, and becomes the greatest pokemon watcher of his generation. His scyther finally evolves into a scizor.
Ash becomes gym leader of Pallet Town, but spends most of his time sulking in a cave in Mount Silver, kicking the butt of the occasional trainer who foolishly seeks to battle him after having beaten the Elite Four & Dragon Master Lance.
Gary becomes Viridian City gym leader, but still occasionally makes the rounds of other gyms in Johto, Kanto, and Hoenn, always beating the leaders. Sometimes he even heads up to Mt. Silver, where he kicks Ash's butt about half the time, and loses the other half. His cheering squad eventually move on to become groupies of whatever boy band is popular at any given moment.