I like to combine the Feywild and the Shadowfell into a single realm called the Otherworld (the cheerful parts are like the Feywild, the gloomy parts are like the Shadowfell). The Underdark is also part of the Otherworld, as are the cloud-castles where giants live, and the aquatic kingdoms unda da sea. The boundaries between the Otherworld and the material plane are subtle and vague; basically, the more magical a place is, the more it is in the Otherworld.
Most monsters and non-human races are from the Otherworld and only visit the material plane, making elves, dwarves, goblins, dragons, etc. relatively rare. The exception are halflings, who are just short rustic people with sturdy feet.
I like to make NPCs skew very low-level, especially with spellcasters. The village priest might have a few cleric spells, and the local hedge mage can maybe cast identify or whip up some potions for you, but a level 5 wizard would be a pretty big deal.
In this way, I can create a "low-magic" world in which "high-magic" PCs can still go on "high-magic" adventures.