For re-prompts: maybe stick to prompts that weren't originally yours (ie. something that you seconded or want to see but someone else thought of it first). Obviously no way to enforce that, but lets some of the heroic prompts of old that are sadly unfilled shine.

Thought B: if you're re-prompting, write the opening line. Filler can use or not, but maybe that one little sentence will get the ball rolling for some (nothing is more intimidating than a blank page).