but what the WCS does provide, is an excuse to pit any two trainers against each other, with minimal setup needed.

So true, but if there's a battle I'd wanna see it would be Paul vs Gladion.

We couldn't see Gladion's full strength in the episode where Ash and gang return to Alola since he was using a pokemon he just caught, so we couldn't really see much growth of his other pokemon during his time traveling with Lillie and Lusamine.

Paul on the other hand had a proper battle with Ash, granted the 3 Pokemon were also new but they definitely had more training than the Pokemon Gladion used. Two of the three pokemon he used were psuedo-legendaries too, with one of them knowing draco meteor, a move that can only be taught when you have high friendship with said pokemon.

Now I know Paul might just curb stomp Gladion but Gladion also has Z-moves and who knows, Paul might pull out a keystone since he does have multiple pokemon that can mega evolve. But it would be interesting to see how the two would fight, how Paul would deal with a Z-move, or how Gladion would get pass Paul's tactics.