Hot Takes:
I find a certain ideas people try to craft very synthetic and unappealing: Stuff like food hats, buildings made of simple panels and fencing, castles made of silos and organs, and waterfalls leaking out of nowhere. It's all just too fake and unbelievable in my mind, and only looks good at specific perspective for screenshots.
And speaking of screenshots, I feel like too many people design their islands to be more like 'photo booths': Lots of attractions that look good for taking screenshots to get internet fame, but their overall town structures are in shambles. I ask people to stop this nonsense, and actually think of the island as a unified whole when designing it.