Basically, it’s all of the things I’ve suggested, added to the game. 
Here’s a rundown of my own suggestions, plus some extra points, not in order of importance :
- An alternate way to use an atlas, like pretty much every other game does.
- An alternate way to write longer messages, and a way to leave public comments about people’s builds
- A way to have more colors per worlds
- More creatures with fun and interesting gameplay and lore tied to them
- A balanced way to repair damaged tools/weapons
- A way to place our power coils with more creativity and freedom
- WAY MORE BLOCKS, like Decorative Gleam or Stained Glass
- A system so people don’t lose pretty much everything they did if their beacon is out of fuel
- Some feature to not feel forced to carry every existing chisels in our bags all the time
- Maybe some blocksets on the in-game store? I’d buy that.
- CLOTHING! Tired of the dirty diapers!
- FURNITURE! I want my build to look like a kitchen from Ikea!
- DUNGEONS! I’d like to have something like that which would feel 100% optionnal.
- Some big re-balancing to reduce the amount of grind and farming we have to do. I just wanna build!
- More fun PvE activities that can be done alone, for the casual player who’s not playing Boundless for the MMO-raiding aspect, and where it’s not “first come, first served”.
- An official modding toolkit to create, import and share our own blocks or decorative objects.
- The mother of all suggestion : A FREAKING ROADMAP!!!
I think that covers all the things my best version of Boundless would have. All the other things already planned by the devs are just icing on the cake.
Except for hard PvE content. I don’t want any more difficulty. I’m afraid the “Hunter” creature is legit going to make me hate the game.