Even if Ash wins, that doesn't guarantee he won't simply continue travelling to Alola.
At the moment there is no time for a Champion League arc unless the S/M anime series gets delayed a little until Ash can complete his challenge.
Definitely don't disagree with you there. I think that even if(when lbr) Ash wins, he'll probably be doing much the same as he always has in Alola - getting badges or symbols to compete in some sort of championship. I guess it just annoys me that people keep saying that because Ash has lost every other league he will continue to lose every league he participates in.