Let’s Go! has featured Pokémon grooming in its trailer prominently, but the core RPG follow up will need to build on that even more. The point of Pokémon is to create lasting bonds with your companions, and too often the core games relegated these relationships to second fiddle as you stored away your favourites to score better STAB and type coverage.
Sun & Moon helped this a little with the introduction of transport Pokémon doing away with HM slaves like Bibarel, but to capture the feel of a true RPG it needs to go further. Imagine being as close to your Arcanine as you are with your faithful dog in Dragon Age: Origins? That’s the next step Pokémon needs to take.
Having Pikachu follow you around was cute in Yellow, and trailers showing Venusaur leaping around after its trainer like a huge toad has already grabbed fans attention.
Hopefully Game Freak will see the appeal of these features. They might not add much to the battling aspect of the game, but they'll make the story live much longer in the memory of trainers from Kanto to Kalos.