@VoidofLight I still say the other games had the problem they just better hid it behind a grind. I'm not someone who is opposed to a grind either. Taking NL for example, grinding bells mostly amounted to fishing all the time. While you did have a lot of rewards to earn over a period of time most of that was just endless fishing for bells to upgrade things and place things.
A lot of people have complained over the years that after a while you just get on and do the same things over and over every day. It's basically a chore simulator. What a lot of people want is just a little more variety to the games.
Lets take the bell grind and run with it. Fishing is good, that's one way to make some money. What about adding jobs to the game to earn money. Work a shift at the roost serving coffee and earn a non-trivial amount of bells if you do a good job. You could add little mini-games for brewing, entertaining customers, etc. Perhaps you work as a tour guide at the museum, or design fashion for the Abel Sisters, integrate HHD so you can decorate other houses for money, or farming. Heck deliver mail to the residents, or expand the randomness of the island tours so treasure hunter is a valid profession. That one change alone would add tremendous variety to the game.
There's a lot of other things to encourage RP and such like allowing interaction with furniture. Throw a pool party, or a dinner party, work out on some gym equipment, or hold a sports game with the animals.
I could write an essay about this stuff but basically you could maintain slow progression but also add this kind of variety so there's always a goal to work toward and it doesn't feel repetitive. There's no need to clone other games but when you look at stuff like DQB2, minecraft, cities skylines, stardew valley, sims, and even some of the harvest moon games you realize just how lacking things are in the AC series. It was great when it first launched because of the novel idea of the real time clock but since then they'd done little to really build on the foundation they laid.