spells for world building
The OC is awesome, there are many excellent modules; but if you want to dip your toe into constructing a module yourself you need to learn at least some coding, and conversation trees were IIRC slow and unwieldy to build.
Suppose instead, after throwing up the broad framework, you simply started 'playing' your module with a PC with a few levels of 'god' and spells like these:
Audible Glamour: text currently in the talk bar becomes NPC's default response
Magic Mouth: text currently in talk bar becomes answer to PC's next choice in conversation
Wall of Stone: creates wall in desired location
Fabricate: place item
Arcane Mark: target item becomes unique
Mordenkainen's Magnificent Mansion: targeted door leads to a newly created map.
Spells like these could be used in normal play as well, but limited as appropriate to your PCs class and level. This would make it easier for people to ease themselves into writing modules.
[edit] On reflection, I answered what I think is needed, but you are trying to work out what you think is needed. I suggest mulling over which books or films contain that missing element; that should help you identify it.
