I understand you have problems with the game, but you are trying to put systems into this game which don't fundamentally don't work in it. After like 7-8 years of development (including both DS and DST), I think it is clear that this game does not have a real objective nor does it want to force players to have one. In that time, the devs could have added any number of RPG-like elements like quests to it, but they never did. You play, you die, you play you eat, etc. The game is whatever you want it to be. Some people like speedruns and challenges. Don Giani, Joeschmo(pls come back we love you), Helicalpuma, and many more, all have incredible challenges that you are free to do. Others like me, even after 2500+ hours just want to make a base, chill, and kill bosses when I feel like it.
Make your world what you want it to be. I'll make mine how I want it to be. You have to get over the fact that the game has no purpose for you. Come up with your own.
That kind of freedom is why I love this game.