Hey there :3

Firstly, I'll talk a bit about your terrain. I really like the idea you have, and it's really interestingly original! However, because of the shapes you've created (the cubes etc), it doesn't really show the terrain skill. You haven't got any curves in the terrain, or a diverse palette (ores are really overdone). Again, I know the point of this plot was to show like an open mine, but it's not exactly exhibiting the skill we look for in terrain. Maybe, if you want to stick with this idea, you could have some sections which show some more shaping, instead of boxes.

Secondly, organics. I do really like your trees, however for the shape of them, I think the trunk is a bit too thick. It only really needs to be one wide, not four! :3 But then you could also have some roots, only short/small or some curve to the trunks!

Lastly, structure. I do really like your structure, however I wouldn't make every layer of the house out of cobblestone. Maybe have one or two of the layers made from a different block (Recommend white wool/stonebrick/oak wood etc).
You could also have more than one structure on the plot! Like on the other side of the cliff, maybe :3

Good luck!
- Dutty :3