DrJawaPhD
Hero
When I'm playing or DM'ing I ideally want a cohesive campaign from 1-20, or starting later / ending earlier if the group doesn't want to commit to that length of playing time.Would you prefer a whole adventure that just takes you from 3-6? Then another that does 6-8. Etc? There doesn't really seem to be a reason to make these adventures (like the DL one) to have you gain power so quickly aside from "Now you get cool powers bro and can fight the Mega Dragon at the end!"
For a published adventure, I prefer short lengths that are easy to drop into pre-existing campaigns. My favorites are the single adventure Anthologies, and then next best would be a couple levels like you are describing.