Again, I’m not saying that FE hasn’t been moving towards fleshing out the world, but other games, like PoR and RD fleshed out the world in other ways. This is still very Persona esque. You don’t need to add fishing, searching for items, and an entire monastery to flesh out the world. PoR and RD did taht perfectly while talking to random civilians and with details in regular conversations.
We learned about characters motivations and stuff through random chats. Again, I have nothing against the Persona esque style, but it’s paramount to understand that this game is very much not a usual FE game. It’s extremely different.
Also: Note, I love Persona. And my fave game is Awakening. Just FYI, incase it seems like an elitist rant.
Aside from that, you’re wrong about the whole “unimportant and just for enjoyment” thing about the monastery.
There’s a 2nd ending in the Edelgard route that effectively is only unlocked if you have their supports up to C and are always talking to her, to a degree. So yeah, that’s not true.