What you're talking about is building the first adventures, not worldbuilding. For worldbuilding, you need to go deeper than that. "Put the village of Hommlet here" isn't helpful. Why put the village in this location? How much detail and depth should this first location have? How much is too much and how much is too little? How big an area should you map out? What relation does this village have to the big cities around it? Is this important for the adventures you have in mind? Do you want to include every species in your world, or just some of them? What do they think of each other? Do some classes have a particular meaning in your world? How important is alignment for your setting? What sort of evil forces do you have in your setting? Where on the realistic-to-fantastic scale do you want to go?
Again, those are adventure building tips--which are, in fact, very helpful!--but they're not worldbuilding tips.
There are plenty of DMs who build a world that exists only so far as the adventure needs it to. And there are plenty of DMs who build a world first and the adventures later. Neither of those is superior to the others.
But my question to you is, why is it so important that an existing world be used for this, rather than creating a new one "with" the players?