A lawn full of geometry is a no-go in Sketchup. Much better to use some transparent grass images like the ones I attached in this thread. http://forums.sketchucation.com/viewtopic.php?f=40&t=25213&p=237473&

I agree with all previous comments, but I would also shorten the road and footpath to the grass line, or vice-versa because it looks like it could be the roof of the building from which the snapshot has been taken. I like it though. Some bump on the walls would help to. And maybe a tree on this side of the house to break the big plain wall.