Using rune casting to determine random encounters?

A while back, I developed a spread of tarot cards to help with creating backstories for players and NPC's, and it's one of the most useful things I've ever done for prep. Now that I've fully incorporated that into my workflow, I've been thinking about rune stones. Casting them onto a blank hex map has been great for inspiring exploration locations, but every time I do it, I can't help but think about how cool it would be to use it for random encounters at the table! Drawing some stones out of a bag, using their positions on a cloth to determine enemy disposition or distance or number of enemies. Using the rune, itself, to determine what the actual encounter is. The only problem is, I don't know how to set it up.

If the rune in this case corresponds to a die roll on a normal table, that kind of locks me into tables that have exactly twenty-eight equally likely options. Maybe position on the cloth could determine what the encounter is, instead? That way, it could be divided into any number of sections that don't necessarily have to be the same size, and the meaning of the rune could affect the encounter in some way?

Mostly just looking for ideas from other people who think the idea is cool! Anyone getting any inspiration?