Overall, this was a fun season. I enjoyed the format significantly more than I expected going into this game, and I'm happy with how well I performed. I did not keep track of my overall win rate this season, but the team was overall rather consistent. I'm looking forward to Season 02 in a week and what access to the Legendary Pokémon brings.
The first thing that I would change will probably be replacing Clefable. I think base Clefable just isn't able to pull its weight compared to the other Fairy-types in this game. I'm not sure which Fairy I'd probably put in its place, but I'll probably consider Base Gardevoir, Sylveon, or Xerneas if Xerneas translated well into Z–A.
The second thing I would change would be redistributing Glaceon's EVs. It does not need all those Sp. Atk EVs, and I think giving it some bulk would be worth it in the long run. I just need to figure out which benchmarks I want to use for damage calculations.
The final change I would make, and this may depend on that Fairy type I run instead, would be to consider running an Assault Vest Gyarados instead and using a different Mega Evolution. Regular Gyarados was just as capable of dealing damage on its own, and the typing change when Mega Evolving means that opponents would have to debate whether they think Gyarados is about to Mega Evolve without realizing that's not an option. In theory the Assault Vest would improve Gyarados's survivability enough where I would not need to change their EVs too much. I don't think Gyarados would need as different an EV spread compared to Glaceon, though.