Yes and no.
I really like the theme I decided on for my island, all of my animal residents and player characters, and all the progress I've made in terms of cataloging, filling up the critterpedia and museum, and paying off all of my player houses and decorating them. It does "feel like home" as you said. If anything happened to the save, I'd simply stop playing the game outright. No interest whatsoever in resetting.
However, I'm not totally satisfied. If you asked me a couple months ago the answer would probably be different, but recently I've gotten the urge to move my Nook's Cranny, Able Sisters, and museum around. I've also been considering possibly undertaking massive terraforming to have all of the residents, who are on the back half of the island, all on the third tier. Having everyone on the third tier was my original plan, but the way things developed in the early days, it led to everyone being split between the second and third tiers. As such, my island is currently in a state of flux and I won't be content and comfortable until my plans are accomplished.
Additionally, to be perfectly honest, I'm not really someone particularly skilled with designing the island itself. Some islands out there are ridiculously elaborate, well thought out, and have nice paths and everything. By comparison, my island is far more natural, there's no way that I think I could make a path system look good with my current setup, and even if I did, it still wouldn't come close to comparing to other people's. I can't deny that some island layouts make me feel that mine is inadequate, but it's not that bad. I don't find it to be something worth worrying about past that initial feeling of "Wow, that island's cool and also something I could never pull off." If I'm having fun playing my own game, that's what matters.