Coming back to this as promised. The first time a room catches fire, the battle now shows a short FIRE hint that says what to do next: send someone in to put it out, seal the doors so it does not spread, or let it die without air. It is live in the browser version on our site now: Void Courier.
Thanks again for the read. If you try it, I would like to know whether the hint shows up at the right moment or gets in the way.