Returning player that hasn’t played in a while, any suggestions on how to spice up a survival run?

So I finally have returned to the old minecrafting mood, my last game I think was back in 2017 and after reaching diamonds, building a railroad network, mining nether and building a relative nice house, my interest died down again. I have never reached The End honestly and I mostly played back during the beta days. That is however why I am here now.

I wanted to check if you have any ideas on challenges or tasks that I should set myself to make the game more interesting? I am really tired right now so I can’t think of much…

No chest or barrel challenge. You are going to use a lot of furnaces!