Weather effects:
1. Clear starry night with the pale moon hanging in the sky.
2. They did a really good job with the Sagoli desert. Apart from the haze, I was really impressed when I went to the southern region. When the sun comes up the entire area gets bathed in scorching light that I start squinting my eyes. It felt uncomfortable but it felt so real.... almost like you can feel the merciless sun beating down on you in a barren wasteland.
3. Heavy rain, where the raindrops get buffeted around in the strong winds. I remember walking into a house and on my way out when the door opened it was raining cats and dogs, then I thought to myself 'Wow it's nice to be inside a house right now'.

Other mentions:
1. Lalafells always standing on boxes when talking to you lol that always cracks me up.
2. Hiding under a bridge while crafting.
3. Two lalafells chatting up a female Mi'qote at Costa Del Sol.
4. Crotch rot.
5. Sunset/Sunrise at Costa Del Sol.
6. Being able to fish from almost anywhere in Limsa (low level fish but still neat).

In all honesty, SE could have done a lazy job and left out so many details. But no, they added in so many things that make the world believable and immersive. It's unfortunate that many players take these for granted and all they care about is getting to endgame and grinding. Why so materialistic?