The Sandbox may be one of the greatest things on Worldbuilding Meta. I recently had a question "graduate" (i.e. people stopped posting helpful objections and I addressed the ones that had been already made). I then edited out the question, edited in the link to the new question, and noticed that there are currently 14 proposed questions (including one deleted one, I think), 8 of which have been posted as questions on Worldbuilding.
That's all very well and good, but the page has gotten to the point that it's unfeasibly long, even with the completed answers reduced to a link. This is partly due to the fact that there tend to be loads of comments and partly due to the fact that there are 14 proposed questions.
As of yesterday, the Sandbox is one month old, so we're averaging 14 questions per month. In the next year, I expect activity to grow, no matter what level the site is at. Even if activity doesn't grow, we'll be at $$12 \text{ months} \times \frac{14 \text{ questions}}{\text{month}}=168 \text{ questions}$$ Plus probably 1000+ comments, if not 2000. This will make the page unfeasibly large. You could argue that one can simply sort the page by "active" - which I tend to do - but people might still end up editing old proposed questions, especially if they haven't been asked yet. It will be very difficult to find a given question (although one could circumvent that by using the search box). This is a good example of a very, very, very long question/answer thread.
So what do we do about this Sandbox Overflow?
Since we're going with the deletion idea, I've created an answer in the Sandbox for links to all the deleted questions.