I bring this up because I find scale in Dungeon World, while useful as an organizing principle, isn't prompting additional ideas for threats the way that scarcities do in Apocalypse World.
I'm looking for that scarcities magic: pick threat --> choose what fictional element it represents --> brainstorm other threats that reflect that element <--> decide how each threat finds expression in the fiction (characters, resources, etc.) --> give it all movement and direction with dark agenda, custom moves, stakes and countdown clocks.
Notice I replaced "fundamental scarcity" with "fictional element" to broaden my perspective. I find I can't just substitute "scale" for "fictional element" and have it work the same way.
For now I think I'll generate fictional elements on the fly based on prompts from the PC's introductions, rather than choosing from a pre-generated list. For example, I'll take the story of The Fighter's signature hammer and the back story I elicited from its player (he found it in the mines, it's a relic of legend, and he had to win many duels to keep it), and think, "what fictional element does this represent?" Let's say "Pride," (in this case his own, and also that of his vanquished rivals). Easy. Pride becomes one of my "fundamental scarcities." I can make fronts about pride all day long.
As long as I guess my players' cues correctly this should work really well, because the story we're telling is then based on the things they've already affirmed interest in.
Thoughts?