The starters will depend on the sidekicks really. If they have a big co-starish role like the Coordinators then the chance of them getting a starter is about 98% since they will want to promote the new character and the quest they do and nothing promotes better then current generation starters. If we get more Gym Leader sidekicks then you can expect to have Ash get all three again. I hope we get another Hoenn situation regardless, one starter for each main cast member but Pokemon in anime form has disappointed me so much these past few years that I'm fully prepared for Ash to get all three again, even if I think the idea is horrible. XY really needs to deliver for me, because honestly, anime wise, this is probably my least region before I drop the show altogether.
Parena or Serecham both equal Serena+Pancham! Sereevee or Serevee equals Serena+Eevee!