I think this game is a mixed bag when it comes to features and mechanics. Some things are so amazingly awesome that I hope they are kept for all eternity forward, while others are so atrociously bad that I hope they get removed from the series permanently and never come back. And some are in-between: good but not perfect, or bad but not terrible.
Let’s focus on the positive since that is what this thread is about. Here are my personal favorites from the features and mechanics in the game. Some of them have already been posted by others but I’m echoing them in that case.
- Being able to nickname your Pokémon directly at the party screen instead of at an idiotic “name rater”.
- The “linear open world” regional layout/design.
- Seamless battle transitions.
- A camera that can be freely rotated everywhere, even in battles!
- The way learning and changing moves work, being able to change (back) to any move as long as the Pokémon in question has learned it at some point.
- Being able to catch wild Pokémon without having to battle them first, but still having the option to battle them first if you want to.
- Being able to switch your lead Pokémon directly on the overworld instead of having to go to the menu first.
- Having a list of main quests and side quests.
- A time system that isn’t tied to the real time set on the console, and being able to change to several other times of day whenever you want (through resting).
- Picking up items on the overworld without a huge text box appearing every single time.
- In a similar vein, not seeing a huge text box when catching a Pokémon, just a small note that the Pokémon was caught.
- Getting trade evolutions without actually having to trade in order to evolve them.
- Being able to evolve a Pokémon whenever you want on the party screen once it has reached the criteria for evolving, as opposed to the Pokémon automatically evolving when is has reached the criteria.
There might be more but those are the biggest ones I can think of. I haven’t beaten the second part of the game yet so there might be more things I like that I just haven’t seen yet.