Thanks - I was going to suggest something like this.
Also, I was wondering if players who resign could have their nations still appear on-screen, rather than disappear completely. They wouldn't be able to access their old nation, but all the tanks/bases/etc would still be in place. I don't enjoy aliens scooping up entire nations and making them vanish.

(It would kind of be like an inactive nation, except that no one can access it. I don't know whether it's a good idea to cancel all treaties as well.)