One of the things I've found myself using is the idea of player's owning things tied to their characters.
The central premise is that a player's character has a sphere of their own. The GM can contribute to this sphere, but the best kinds of RPG campaigns tend to be grok-worthy when players maintain, create their own spheres and interact with other player's spheres as well. Some NPCs and items belong to a particular character. I the GM could exercise "ownership" over all the NPCs in my game- but splitting the onus of ownerships makes more sense to me, on philosophical and practical grounds.
When talking about "ownership" I mean the basic creative dimensions to a character. Can the character die? Who is allowed to mess with the character? What is appropriate and not appropriate for the character?
This doesn't mean that I double check every little thing a NPC says or does with a player to make sure they are doing what they are supposed to do. Instead, I expect players to help me find the boundaries and keep to them. I try to actively complicate the NPCs lives, but I never remove them. The players and their characters get to define the nature of their relationships, and I build on that. In turn, a player will build off I've done.
But as a matter of trust, I let them own the things and characters within their "sphere" of influence. In Fate Core, this has a simple way to tag NPCs and objects the players have control over. One way I've done it is to inform them that spending a fate refresh for a Extra that represents a magic item also makes that item "out of my reach." That is, I won't have someone steal it, take it from them or destroy it. Even outside their possession, the player's character "owns" the item. It's theirs to define and direct.
This approach combines trust and creativity. It's still more of a way of thinking. But it is a cornerstone of my current thing, sliding along with other ideas. Players (GM included) should feel some sort of ownership in the characters they play. That seems critical to me. The other cornerstone is pushing away as much as I can from using violence as a default mode for "excitement." Ownership can help to reduce (or eliminate) violence as the main means most players think of NPCs around them.