I don't think he will ever be a Pokemon Master. He couldn't beat a newly hatched Snivy with a Pikachu that in the games would be lv.100. I think It will end somewhere in Kanto. Misty and Brock will both make an appearance and possible May, Dawn, Tracey..etc. I think it will end with a extended show, possibly a movie. Ash or Pikachu will have a near death experience and it will be a real intense episode leaving you at the end hanging wondering what would have happened next.