I’ve had most of the previous games and I would always need to look up how to answer the questions given at Shampoodle get a certain hair style in ACNL. I was thrilled when I found out that you didn’t need to do that in this game!
Tangentially related with Shampoodle: I really love getting to change hair cut and color, nose and mouth and eye shapes, and eye colors at will. I love playing around with my in-game appearance, and as someone who's non-binary, it's nice to be able to alternate between eyes with/without lashes! But even aside from that, it's fun to get to change my hair multiple times a day depending on what looks good with what I want to wear (I typically cycle between 2 colors and 3 styles). I hope in the future Harriet does something like coming to visit to run hairstyling classes, and selling color contacts (and maybe other things but that's a different topic), because they did cut one of my absolute favorite hairstyles from New Leaf.
Outside furniture is definitely my favorite thing. It allows for so much customization and is such a huge improvement from previous games. The PWP system from New Leaf feels painful in comparison.
Being able to decorate outside with (almost) any furniture easily instead of PWPs makes the village truly feel like it belongs to me and it's so great to just sit back and admire my hard work (even if I hate it a day later and rip it down :,) ) I know this was said by most of the other replies but it really is an amazing feature.
Being able to move around all houses and (almost) all buildings is nearly as amazing though. It's just so crazy that we have the power to do that! It was absolutely painful trying to line houses up in New Leaf, even after the Welcome Amiibo update. Because you could have what seems like the perfect map after hours of searching; Retail and Town Hall in a great spot, the kind of beach you want, etc... but there was always that one gosh darn rock! Worry no more!
i really like that we are not stuck with our starter map and can change just about everything about its appearance. i'm also a huge fan that the cliffs came back (idk if it counts as exactly new) and of course that you can put stuff outside.
i'm also a HUGE fan of being able to break rocks as they were always exactly in my way in acnl. i cursed them out so much because they were always in my path
Being able to choose a place for your villagers' homes, it's honestly the best! I still remember how annoying it was that villagers could just move in in the middle of your path or flower garden in new leaf for example. I'm very glad that they changed it in a way that feels like a part of the game ☺
I like being able to move most buildings etc because back in Wild World I’d end up having to reset if my shops were in a weird place!
That and being able to pick how you look at the beginning instead of answering a series of weird questions!
I love the ability to terraform! saved me so many hours of resetting in comparison to New Leaf. although I equally hate terraforming because it's so tedious and I'm bad at it ahaa
For me, the best part is being able to store furniture outside. I love decorating in games like Happy Home Designer and was so excited for this feature.
Other than that I like that the villagers sing and interact with some of the furnuture you've placed, terraforming, and CJ
The villagers being more interactive with stuff outside! And their hobbies being more pronounced... I love it so much to see them reading, doing yoga, etc.
I also love how we can move all the buildings around... Really hated the villagers being able to put their house wherever in NL, at least in WW there were designated areas where houses could go :/ that was a real step back that has now been solved entirely.
being able to place furniture outside is just *chefs kiss* - i also really like fish bait! it’s a pain to craft a bunch of it but it’s still very useful!
Being able to move buildings is AMAZING! And changing your clothes is so much easier instead of taking icons that all look the same out of storage and trying them on and then having to out everything manually back in storage again. ALSO, it's such a small thing, but not being automatically greeted everytime you enter and leave a shop. AND! Being able to see items like wallpaper and flooring, bush starts etc in stores without having to click each item individually like it was in NL .