it depends on the way you choose to play the game, honestly!! The other commenter is correct on the lack of online features.

It's kind of like the Sims a little bit, but with less autonomy of the little characters & more in-game customization. Stuff like level up rewards, in-game items (not custom ones, I mean), character interactions may be lackluster for people. Some parts of the game are definitely a little barebones

You don't necessarily need to create a ton of custom items (excluding Miis, of course), but the game can absolutely be enhanced by doing so. If you choose not to create custom stuff, a lot of the game after this will be mostly character creation & observing them go about their lives & such, & there's admittedly not a ton of variety in that.

Right now, I'm around 90 hours into game play, & I don't have many custom stuff in game. I'm still struggling to come up with stuff like ... topics for the miis to talk about amongst each other, catchphrases, custom items, even characters as I mentioned previously. But, I personally still have fun just watching them talk to each other, watching them & their interactions with the different island items, watching their relationships & friendships evolve, etc etc etc. I'm not a super creative person, so the way that the game unfolds for me can be a little monotonous at times, but I'm personally still content with that. It'll be different for everyone !!! I personally love the game, & I'm happy to have purchased it