Patrons, those social anchors and quest givers for the wandeeing murder-hobos we call player characters.
From nudging players into action via quests, or rewarding success, to providing the social context for why killing that bad guy doesn't get the town guard after you but shaking down the bigger kid does, patrons should be a big part of fantasy game. A society even remotely based on a medieval world view wouldn't allow for most of the shenanigans that PCs get into without a powerful patron to give political sanction to those random bouts of physical violence and the liberal misappropriation of monies players are prone to.
So what does that mean in a game? Well first off the Patron should color the group, be it political views or fantasy religious habits.
This is a big deal because its a way to guide the party template. If you don't know what the party template is you really owe it to yourself to check out Fear the Boot. Go listen here
In a nut shell its the logic behind why a group of player characters would risk their lives with other nutcases while going out and risking their collective necks. So rather than pretending there's a floating invisible mark over the heads of just some people which means they're somehow trustworthy, you instead create an artifact that explains why people are together.
This is where the patron comes in. In WHFRP game I'm planning the characters will be defined by which patron they all decide to serve. This will also decide what plots I focus on developing further.
For example, picking a patron that is a member of the religious hierarchy of a major faith, like the cult of Sigmar in WHFRP, would give a party a fairly significant inroad with the faithful, access to at least some level of political shielding, access to some significant finances and hopefully some access to magical healing beyond the norm. However on the other hand they'll be expected to act to further the plans of the church, be it cleaning up awkward messes or recovering relics from dangerous locations. The focus needs to be on opening up new venues for the players, rather than limiting options