If you're on the writing team I recommend carrying around a notebook or be prepared to take notes on your phone. Something will strike you and you will forget about it the moment you turn your attention away. Heck, I had that graveyard thought in the car and almost forgot about it by the time I got home and cut and pasted the others. The frustrating part was that I knew I had an idea, but couldn't remember what it was.
Comedy is the most difficult writing task because of the density of the ideas involved, but look at it this way: if we make the BroQuest writing sharp and funny, it will be in rare company among video games. If we start taking our ideas as they come now, the script will be vastly funnier when we sit down to write it. So if you think of something funny, post it up, whether it's just a clever item description or a massive, epic arc for the sake of a brick joke.