Didn't I hear about a lawn mower item that can remove grass? My guess is that grass wear is brought on by either a lawn mower, or a building being removed and leaving a spot, and that grass doesn't grow back on its own, instead you would use a grass seed.
That would be ideal, let's you choose...
I watched one video of someone creating a town, and it appears they were given the option to tell Rover that the map he was showing them is incorrect, and he showed them a different one. I wonder, how many times can you "correct" Rover and try for a preferable layout?