While not a base editor, it allows you to save your base layout once you've built a base layout manually. Then you can change back to it whenever you want to.
For example, you can create a base layout to defend Hammerman and another base layout to defend against other players (even though the former cannot be encountered until you reach HQ15 at least). Then every Monday, during the Hammerman event, switch to your Hammerman base for the event and then switch it out for your regular layout once you're done with the event. You won't have to manually build a base and drag buildings around for that purpose every Monday.