Thanks for the warm welcome, it's much appriciated.
I can't believe I saw the F6 icon and that you could plant trees but still not managed to make the connection of planting plants.
From what I understand a lot of problems could be solved by simply allowing players to decide the size of the map and whether they need a surface level or not. Think about it, from a map generating perspective, the former is about making a bigger box, while the latter is about filling said box completely (and maybe adding indestructible rocks so you can hit the box and not fall out of it).