10 Things Pokémon Sun & Moon Must Fix From X & Y
9. Scrap The 3 Vs. 3 Battles
Larger battles were introduced to the series prior to X & Y, but they were a larger feature than ever in the sixth generation. Considered a way to increase the action in a fairly formulaic series, it's easy to see why piling more Pokémon onto a battlefield could've been seen as a reasonable move to make.
In practice, however, these larger battles only served to point out some of the flaws in the makeup of the series. For starters, in regular 3 on 3 battles you'll find certain Pokémon are only able to attack their counterparts if they aren't too far away. This makes the game feel terribly stagnant and removes any illusion that you're participating in the kind of exciting, dynamic battles seen in the anime series.
They also highlight how important chance can be to a battle. Placement becomes everything, as if you have a strong type-match that isn't well-positioned at the start of the battle then you may not even be able to make good use of it. It could be argued that adding a shuffle mechanic to these battles could help save them, but ultimately they're an addition that wouldn't really be missed if removed altogether.