Some ideas from me and/or some others: More buildings (bed, crate [a cheap chest with less storage], strong pillar [a much more expensive version of the pillar that can hold more floors], ladder, door, fences), a new rare item (crashed plane part/crashed boat part: a very rare item used for crafting), diving with new underwater items (corals, stones, fishes, crabs, squids for ink (a crafting material) dangerous animals like a ray or a shark and some other things), a new plant for medicine, achery and maybe a backpack.
I think some/many players will be extremly happy if you add some of this suggestions.
Sorry for my bad english but im not from america or other english landscapes.