This is game is definitely one of the best Pokemon games, but that being said, I still think it is a bit overrated. It doesn't have any major flaws, but the occasional backtracking, difficulty spikes, and the general plainness of the region hold this game back for me. It does also have some really great new inclusions though, such as reusable TMs, repel prompts, and animated 2D sprites for all pokemon.
I am a big fan of Pokemon XD and its battle CDs, which are like tiny pokemon battle escape rooms where you use rental pokemon. I was very excited to play the Pokestar Studios missions after learning that they are essentially the same thing. However, I was in for a rude awakening when I found out that Pokestar Studios' battle puzzles are tainted with heaps of RNG. Even when performing the "solution", turns are prone to going wrong because the enemy actions are not predetermined like they are in XD's battle CDs. This made the mode extremely frustrating and is my personal biggest disappointment in this game, and I stopped playing them after the first 5 missions. I can see most people not having any opinion on Pokestar Studios inclusion at all, but I do think the failure of this game mode is a negative to the game's overall experience because it completely fails to deliver what, at first glance, appears to be a really fun side mode and you are also forced to sit through a pretty long interactive cutscene early on in your adventure.