Many actions have to be repeated many times when dealing with many items, and currently it requires one mouse click per item. This usually results in boring mouse-clicking for a quite a long time. Many games have implemented a way to deal with lots of items. i believe DST needs this as well, especially since it's multiplayer game where people collect way more stuff than single player would ever do in DS.
I tried to make up a list of actions which need automation, provide examples as well as include possible solution.
a-c apply to 1 and b-c apply to 2.
a) Cooking over fire. Most frequently it applies to cooking monster meat to later turn it into eggs. Imagine that you have to click on fire X times for all X monster meats u got.
b) Feeding something to a bird in birdcage.
c) Giving pigking meats & trinkets for gold.
1. Doing action related to structure. It could be done via holding down space button while also carrying items in hands (outside of inventory) standing next to the structure.
2. Picking items returned by the structure. Here, I suggest to make those structures return items directly to player's inventory instead of dropping them on the ground, because ultimately they all will have to be picked up by the player.
(I know that it can also be improved in many ways, especially through modding, like making some kind of dispenser which automatically does the action related to structure it is placed next to, as well as gather items returned by this structure.)
3. Crafting items which are often needed in large amounts, like ropes, boards, cut stones, gunpowder, tooth traps, walls and so on. Possible solution would be adding "Build All" button next to "Build" one. In this case players will have to be cautious to drop stuff they don't want to be crafted, though I believe it will take way less time than manually clicking "Build" button to craft every single item.
4. Harvesting farmables. I can't come up with simple solution, rather than using lureplant, even though it requires special spacing for farmables, due to relatively unpredictable pattern of eyeplants spawning. So, one idea would be making new item crafted from lureplant, that will somehow harvest stuff within its woking radius without eyeplants (possibly using animation like shadow stage hand coming from the ground).
That's all that came into my mind as of yet, feel free to reply in comments if I forgot something. I hope some of those will be addressed, especially since we have been shown that developers actually read feedback, taking into consideration the fact how quickly they fixed lantern exploit after just single person reporting it comments section.