It's the way they keep the show on the air. If Ash becomes a champion, what other adventures would he go out on? It appears as though they are trying to keep the spotlight on Ash and Team Rocket. I hope they change it soon; a change in main characters would be refreshing.
I stopped watching the anime because the episodes seem exactly the same; a new Pokémon appears, Ash tries to catch it, but misses. Ash meets someone related to the new Pokémon, Team Rocket appears and tries to steal the featured Pokémon along with Pikachu; the featured Pokémon attacks Team Rocket and they blast off. End of show.
I don't think 4Kids' tenure expiration will do anything to the plot of the newer episodes. I can only hope that Nintendo will get a little bit more original with the newer episodes and try to appeal to somewhat older audiences.