Idea #1 - Iris meets, befriends and catches a Lapras. It would tie her in with her B2W2 counterpart and serve as a character building episode for her, helping her to get over her fear of ice types a little. I know Ash owned a Lapras, but this sort of thing did not stop Solidad from owning one, along with a Butterfree and Pidgeot. Nor did it stop Drew from owning a Butterfree, May from gettign Bulbasaur and Squirtle, Dawn from getting Quilava or Barry and Conway from both getting Heracross. So it could still work easily.
Idea #2 - Gary and Paul come to Unova and challenge Trip and Cameron to a double battle and show them how a real rival of Ash's is supposed to battle!
Idea #3 - Stephan catches a Golduck (am I alone in thinking that this would be an awesome pokemon for him?)
Idea #4 - More of a mini-arc idea, I suppose. The world tournament happens and Ash challenges it. Features appearances by all past gym leaders (including Misty)
Idea #5 - Bianca begins working as Juniper's assistant. They meet Fennel who's Munna gets attatched to Bianca so Fennel gives it to her.
Idea #6 - Cilan, Chili and Cress get together and evolve their monkeys, just because.
For anyone interested, by friend code is 5257-9947-2315. If anyone wants to add me, remember to PM me so I can add you too.
My friend safari contains the ground type pokemon Phanpy, Marowak and Palpitoad.
Current Y team consists of Delphox, Pidgeot, Raichu, Simipour, Charizard and Gogoat.
In training: Wartortle, Bulbasaur, Chespin, Froakie, Combusken, Pangoro.