Yeah, the game's story line is definitely meatier and more nuanced if you compare it to the previous generations, and it's a change that I truly appreciate. The trials are fun l for me though, no matter how goofy and sometimes awkward they are if you're not expecting something.. 'serious' out of Pokemon games. I needed some time before I felt fully comfortable with the 3D model - I swear my eyes were straining during the first couple of hours of the playthrough. I also love how they ditch HMs, which is the most important change in game mechanics for me since HMs are just terrible and constraining. I finished it in 25 hours- ish, which is the longest time I needed to finish a Pokemon game, I think. Oh, it's also worth mentioning that post-main story line contents are definitely much better than prev gens too, really glad the developers listened to the complain.
If there's anything that I'd like to whinge about is how the 'tutorial' part of the game is pretty tedious and unnecessarily long.. even for Pokemon beginners, I don't think you need that much of an explanation during the early game.
By the way my team when I finished the game (1st Hall of Fame) were: Decidueye, Inceneroar, Primarina, Lycanroc (Sun version), Metagross, and Garchomp. IME, the most versatile Pokemons in my team are Primarina (you can teach it energy ball, for example) and Lycanroc, at least in PvE context. I was using Mudsdale and Kommo-O to at some point, and I believe they're pretty powerful too.