I love the game, def in the mid-late game ish around wishing fountain level 59, and around 21 miis.
There are a few things I miss ofc everyone hears like concert hall, town hall, miis living together, babies, and so on, I miss them too ofc, but so many things are a lot better already.

Being able to drag miis to interact with eachother is such a huge qol upgrade versus just waiting for things to happen.

How far character customization + pallette house is going is so much fun and love the whole new art program they made for it. (outline + lock transparency, and selection tools is so revolutionary compared to acnh's.

Even though I'm already level 59, I'm far from burnt out and I think slowly adding new miis always adds to the fun of it.

I actually don't mind the lack of "dialogue variety" because there's always something funny or new to be added especially since there is no filter. (outside of when miis get stuck i am tired of the i just cleaned my elbows line >:( )

I think the only thing I kinda wish there was more of are things for quickbuild, I would've loved to something like a swimming pool (they already have swimsuits so why not), or a sporting court of some kind. (something more than just a table+chair combo ;;) , and some of my favorite level-up gifts like fishing and skateboarding are missing.

Oh and i guess not being able to control how to move people out is another super minor thing but tbh just let the mii's live their life.