Well, I wasn't sure to comment on the mapping or not, as it may have been only a test for the tiles.
But, yeah. It doesn't look natural, everything is quite stiff and square, for instance, you can make that body of water look more natural by adding some twists and turns to the silhouette. You can make the scene more organic by scattering the trees properly, rather than aligning them to the edges of the map.
Do the same with the 'details' the flowers and bushes and such, it's almost as if it's a painting itself, scatter them properly, don't, for instance, hug the tree-lines with a certain flower the whole way across, make it look realistic.
Right now you have one big square for the body of water, which is hugged by a 1-tile thick border of flat grass. You have a straight vertical line of trees down the left side, and the left and top sides of the map also lined by white and red flowers. Pretty much everything else is covered just by the little leaf things. Anyways those are just patterns I noticed.
It's a step in the right direction with the smaller tiles of the white flowers, spreading out from the edges of the map. I also think, maybe the road needs a little more attractive transitioning into the grass. And your house design there needs a bit of a thinking over.
Honestly, though it's not bad stuff, there's something about your trees that I love, although I'm not sure that they quite look like trees. And I second everything Adarias said.