Heh see if I was doing the story for Sun&Moon, I'd have Ash catch Rowlet(and evolve it!!), Litten and Rockruff. Poipole was a surprise and I still haven't made a decision on his 6th member but I'm leaning towards Alolan Sandshrew/Vulpix(An Alolan form would be unique for his team).
I'd have Lana catch Dhelmise, Dewpider, Lapras(Rider), Wishiwashi and Vaporeon to go with Popplio. Kiawe would have Alolan Marowak, Flareon, Charizard(Rider) and Salandit to go along with Turtonator. Mallow would have Lurantis, Oranguru(she had the opportunity), Alolan Exeggutor, Lilligant, Whimsicott and Tsareena. Sophacles with Alolan Raichu, Vikavolt(evolve Charjabug already!!), Alolan Golem, Jolteon, Lanturn and Togedemaru. Finally Lillie would have Alolan Ninetales(starter), Clefable, Klefki, Shiinotic, Sylveon and Solgaleo(aka Nebby).
That would necessitate a capture almost every damn Episode :D