Hey there :3

Firstly, terrain. I have nothing bad to say about it! I like the multiple layers you have and the palette you've used. If I was to say anything, it'd be just to recommend mixing some more ice in the snow/stone like you already have done. I'd also want to see some more 'decoration', to add atmosphere to the terrain. You could make some rocks/frozen ponds etc.

Secondly, organics. Your large tree is really great, but the trunk needs some smoothing. It looks a bit too jagged right now! I also think you need to add some more layers to the roots, so they're not all flat!
As for your smaller trees, you need to make the leaves a little bushier - it may be easier if you add some more branches.
And as you have //replace, why not change all the logs to 6 sided logs? cx It might look nicer.

Lastly, structures. The structures you have are really cute and suit the style of the plot. However, as they're quite simple, you're going to need some more on your plot; maybe a tower so it's taller, or at least a larger biuld somewhere?

Good luck!
- Dutty :3