Brainstorming Background Ideas for a Composition

Part of telling a story with a painting is using the background to give specific context to the figures and their actions. I've found one great tool for brainstorming background ideas is Procreate. I can pull an image of a drawing into Procreate and then use layers and various other tools to play around with different ideas. This is a very powerful tool, and it's also a ridiculous amount of fun.

One fun bonus of this process is that Procreate automatically generates a timelapse video of the process. 

Before using Procreate, I used to use a similar process by printing out small, thumbnail copies of the figure drawing, and then sketching backgrounds on those. I've also done a similar thing by roughly sketching an outline of the figures in ink, and then sketching background ideas over the top lightly in pencil. 

Regardless of the tools used, the thought process is the same. How can I give more context and meaning to these figures, and how can I more fully explore my theme with the addition of a background?