Hey there! :3

So firstly, your terrain. I like the variation you have, in both the grass and the stone parts of the terrain, even though the majority of the grass area is way too flat. However, I do feel like you've taken up too much of the plot space with the mountain - this would be okay if you included more on the mountain (I'll get to that later).
I'd also suggest changing up the palette for your mountain a little. I wouldn't use ore blocks, I'd use stained clay/cobble/andesite etc. I'd also suggest not having the snow 'carpet' block only on top of the mountain - use full block snow, and don't have a clear line where the snow starts/stops; make it quite graduated.

Secondly, organics. The trees are far too square. Make the trunks curvy and taller, with roots and branches, of various sizes. Check out Plutouthere's YouTube channel for his tree tutorials.
You have world edit too, so I'd suggest to make the leaves, using a command like:
//br sphere 90%air,10%leaves
And follow the branches, till you meet in the middle. This gives much more of a natural feel, and makes the shapes a lot less square.
You could also build some larger trees on the mountain, or some kind of animal organic - that'd fill the space more, and would also show much more creativity!

Lastly, structure. I like the large house you have - it shows a nice design, but no depth or detail. This can be added by biulding the logs one layer out to the planks. You can then add stairs/slabs for detail, or trapdoors/fences tend to look good on small houses. I'd also suggest a change to the roof - use full blocks instead of stairs, and have the layers of the roof come out one each time, instead of how you have it now, where you have only the top layer of the roof coming out.
Once that's done, more structure around! I'd suggest also a large structure on the mountain, maybe a tower.

Good luck!
- Dutty :3