Many suggestions, part 1
Where do I begin, I have quite a few.
1. increasing the amount of marks on certain quests and for things such as keeping the center lake drinkable, make the reward high to nudge people into replenishing the lake more often. It will urge people to want to do the quests because they want marks and to be able to drink the water.
2. Removal of certain items from the Home cave store in favor of being able to collect and bring items to the cave. Yarrow, Lychee, ginger, things already pick-up able in the game can be brought in and "planted" in the cave but if you want higher quality stuff such as large rocks or crystals then you would have to go to the store. It will promote more travel around the map and give the quest items more uses.
3. more diet diversity, another use for quest items, have nut eaters, fungivores, have the forest feel like a more bountiful place for foods and have it be an ability they work into for these items.