Looking to build a high fantasy world, with the same sort of feel as a ‘D&D’ world such as Golarian or Faerun.
It needs to be High Fantasy - magic is common enough for player characters that they can be wizards chucking around fireballs and summoning elementals, there are magic swords and rings.
Magic is not too common though, and the average person doesn’t have access to it. Most villages probably don’t have anyone capable of using magic. They might have a herbalist, but no actual spell casters. This means disease, drought, starvation etc are still common threats. The rich don’t need to worry about them, because they’ll have a spellcaster on tap.
There are plenty of non-human monsters to hunt and slay. There’s a reason for them being there, and why there’s such a huge variety.
It’s a mostly high medieval culture, with a bit of magic (flying cities or clockwork armies aren’t common). Gunpowder weapons may exist, but they are limited in availability.
Large cities exist, with populations approaching ancient Rome at its height (a million or so). Big city adventures become possible. There doesn’t need to be many of these though.
Also ancient ruins and fallen civilisations to explore, and a reason for them to exist.
There is a wide variety of different cultures, to allow for gaming in all sorts of different min-settings. Barbarians, Roman Empire, Egypt, Renaissance, Chivalry, Horror, Pirates etc.
There are a lot of different humanoid races as well as humans.
Possibly no creator gods, but lots of ‘Powers’, which for all intents and purposes are gods. There may be outer planes and the like.