Yikes. Seeing a lot of contrasting points of view here.
I thought the episode was okay. Great for continuity, save for no mention of our XY group or a certain Pokémon that I was hoping to see...
Gengar jobbing here did suck, I won't lie. Hopefully, he gets his chance to shine in another episode where he gives Ash a win to increase his rank. Speaking of which, congrats to Ash! He now has four Pokémon capable of battling Mega Evolutions.
And seeing Dragonite in an official battle for the first time was awesome. Great to see that she's fierce on the battlefield, but is still a softy at heart afterwards.
Didn't really care for Goh here. Cool that he got some more Pokémon, but not really much to say about his goal in the episode.
I have to agree with @dman_dustin
about the series feeling too episodic. It just feels like it'll be paint by numbers in terms of what happens: Ash gets into a battle and Goh catches new Pokémon that we'll never get to see again.
Oh well. Next week looks... interesting? Um... I might just skip next week...