Personally, I gave my answers in these two threads : [CRAZY IDEA] Bunch of Gob's Gameplay suggestions & [CRAZY IDEAS] Bunch of Gob's Building suggestions
Just the things in the building thread would change everything about how I look at the game.
But the Holy Grail, I think, the ONE THING that will allow a game to live on for many years to come, is the ability to mod the game with player-made new items / weapons / blocks.
That will never happen in the Live Boundless Universe simply because of PSN.
The only way something somewhat similar can be achieved the way the game currently is operated, is through the contests to have player-designed props/blocks re-made by devs for the game. If that could happen on a regular basis (like even once a year), that would change things.
Many years ago, I remember the people from Creativerse had a Block Madness event on Twitter where they made us vote by brackets for the type of block we wanted in every shapes (since CV doesn’t have chisels, every block doesn’t have a stair or slab shape).
From what I saw, people were really excited for it, there was actual team pride. I was Team Adobe Bricks myself. It was fun.
Imagine if Wonderstruck actually made their community vote on what they prioritize next.
How crazy would that be?