New plane number 173 will be a Craftsman riding mower. When there are no missions, we can mow that grass, pick up the trash, and make it all pretty. 
Not a bad idea at all! AH could attract some of the Minecraft folks. In fact, why not let players build additional defenses such as pillboxes, AAA stations etc. around fields?

Imagine the fun of bombing someones 1 month work to smitherines?

On the flip side, bored players could build a 'maginot line' behind the front that would have additional fortifications to beat before bombing to submission.