1# Once you've mastered ships with several players without bugs, make an endgame content that requires a flying ship to reach (you can't fly that high with the potion of flight or propeller backpack! The ship has to be very hard to aquire (Magic sails maybe?) and a special magic ingredient that requires you to kill several bosses on all the different islands. One of the ingredients are located in a tall mountain snow biome that gets super cold with lots of Wolves
Once you have the ship, you can reach the islands in the sky, which has new bosses, better loot and new biomes with magic unicorns!
2# Make the chain saw chop down trees on click and not on hold so you dont have to hold it down. It gets really tiresome, and feels a bit pointless.
3# Make it so you can loot while holding down so you dont have to click over 9000 times.
4# Add a destroy button to items that can break, and make it destroyable with the use of one mouse click. Clearing Inventory takes way too much time!