I think Zorua would work well :] Or Zoroark, though I'm not sure if a rare Pokemon like that would be caught by him. I also think Starmie would be cool or Erlade(Gallade). If Hikari didn't have a Togekiss already I'd easily suggest him to get one of those. I really would like Starmie for him though, Kasumi's went largely unnoticed so it shouldn't be a problem. He could catch said Pokemon in the Stone Evolution episode.