Since I've got night time I just HAD to add coloured lighting!

There's a day/night cycle. While it doesn't effect you, NPC's and animals like their routines and will go to sleep when it's late.
If NPC's have a house they'll even head home before going to sleep, alternatively they can sleep in a Dormitory can't receive buffs from it. Those without a bed at least have their sleeping bags to stay cozy.

You can eat food to replenish your Stamina, or to gain Status Effects, not all of them good...maybe try cooking the Cactus before you eat it?
Also, if you don't have a Tool handy you can always try rolling into a tree X'D
(Old gif)

Plant Pots retain water better than Tiled Soil, but require Flooring below them before you can craft one.
You can place them indoors allowing you to protect them with Roofing. (Maybe they grow faster under Glass??)
You can also Plant fully grown Flowers into a Plant Pot for decoration
(Old gif)

As well as getting the Goblins to do it, you can grow Plants and Cros yourself, both in Tilled Soil as well as in Plant Pots.
You can also use a hammer to

Also got a basic Fishing system set up. Different Fish can be found at different depth levels, as well as different locations. You can even fish in The Underground if you can find some water down there!

And I've got a Weather System! The Island is split into Chunks, so there can be different weather conditions in different places.
It didn't feel right to have weather over the whole island.
Weather affects the ground, such as Snow piling up, Sand becoming wet (Shovel to collect!), or watering plants!

There's also Animals on the Island, which of course you can pet and befriend!

NPC Buildings have their own menu which allows you to customise their shape, appearance and furniture.
(Whoops! looks like I forgot to exclude buttons and minetracks from the floor type list X'D)

You can build many things, including Walls, Floors, and Doors allowing you to make your own home, but I also included Prefabricated Buildings for NPC's to use.