Taming Verbosity in Scenario Writing

There is a quintessential problem with writing up an RPG scenario that can be used by others rather than by yourself. When running the scenario yourself, half (or more) of it is likely to exist in your head, with only scant information
written down. The Angry GM says it thus:

The difference between a homebrew adventure you plan to use yourself and an adventure module you plan to share with the world is that, when it comes to a homebrew adventure, you’re done when the design's done. Once you’ve sketched out the maps and flowcharts and have a goal and a plot and some encounters, there’s nothing else to do. You just take that crap to the table in whatever form works for you and you run it.

With a module, you can’t stop when the adventure is designed. Because you have to present the design to someone else in a way that lets them run it at their table with their players without you there to help. You have to explain the adventure to someone else. You have to tell the GM running the adventure how it works. It’s a whole extra step. And that step involves putting a lot of words to paper.

The "putting a lot of words on paper" part is not only time consuming for me as a would-be author of an RPG scenario (this is a side project, after all), but too many words may also be off-putting for the potential readers, who probably do not want to read dozens and dozens of pages in order to run a scenario.

The grandmistress of writing scenarios that provide the reader with all relevant information in a minimum of words is Kelsey Dionne of the Arcane Library. In the introduction to her scenario "Temple of the Basilisk Cult" (which you can get for free, if you sign up to her newsletter), she says:

This adventure is meant to be run at a glance with minimal preparation and a natural delivery. This required re-thinking the normal adventure presentation a bit. Here’s what you’ll find included:

• Each encounter contained on one page.
• Bulleted lists. Bolded keywords.
• Hyperlinks to monsters and rules online for quick reference.
• Printable cards for each monster and PC so you can run encounters using a card stack.
• Short room and area descriptions. No paragraphs of droning flavor text — set the scene naturally and embellish as desired.
• Briefly explained non-encounter rooms. Again, embellish as desired!

That is definitely the direction I want to take, but I'd like to take the whole thing one step further. Kelsey's scenarios are structured around encounters with clear segues. I, however, enjoy scenarios with many different NPCs the characters need to interact with. How to present information about multiple NPCs in a way that still makes it possible for the GM to run the scenario without spending hours and hours in preparation?