Here's a quick edit :

*Added some shadows to give the house a less flat look
*Outlined the house a little bit more clearly to give depth and define the borders of each surface
*A few "misplaced" pixels fixed
*Added icicles to give the house a less flat feeling
*Gave the tree a more realistic look
Hope that helps, great job other than that!

*Added some shadows to give the house a less flat look
*Outlined the house a little bit more clearly to give depth and define the borders of each surface
*A few "misplaced" pixels fixed
*Added icicles to give the house a less flat feeling
*Gave the tree a more realistic look
Hope that helps, great job other than that!