I think the picture is good and the idea great. But I also think the line between the grass and the path is too straight. Perhaps you should try other textures? A dirt/sand like texture could perhaps soften it up and then you can put patches of grass irrigularly over the path to make it look more natural. Also try to snatch some tree textures form the free-section - they are great for making the trees look natural....the default texture is not all that great. But actually I do like your picture anyway! :-)