i think, players think they want some grand plot behind it all, but thats actually not it. i think players want mostly two things out of "the plot"

• they want to discover connections, and that's something i can easily provide as we go along by looking back at what happened in previous sessions and tie it to something they are interacting with now.
• they want the feeling stuff is happening in the world

and by for example having crates with the sigil of some noble they did not like turn up in a cultits lair i can achive both. and i have to prep less stuff that never comes up at the table and when i can't decide on what exactly to do i can allways role on my list of factions/npcs to decide that.

yeah, Sir Peters Guards always had dealings with the thieves guild... let's put one of his men in the hideout with a bag full gold or let them find a blue print of the Mansion of Sir Peters rival there.

that way factions and their relations grow some what organically without me having to invest a ton of time into something that might be used and those random encounter tables so many people dislike are suddenly super cool and useful, because i can use the freaking bandits later if they encountered them.