I kinda like that the game is unfair at times. This is a game that plans to include all pokemon. So having an extremely difficult game to the point where all odds are practically against you really forces you to use every aspect of the game, whether it's new moves, items, or even pokemon you wouldn't normally use, to overcome challenges. I'm really hoping this trend of difficulty stays.
However, what I do hate is how certain stats in pokemon, like their abilities, are randomized per battle, even during trainer battles. I experienced this first hand when the Grass Gym Leader's Serperior had an amazing set up of Leaf Storm, speed IV/EV, and Contrary ability. Only to beat the it after resetting a few times to the point where that same Serperior didn't have contrary anymore, which totally killed its build. This means you can actually stack odds in your favor by simply soft resetting until the pokemon you're stuck fighting against has its stats randomized to the point where it's non-randomized move set becomes significantly weaker.