It's a neat hack of the old BX stuff. I was originally very confused by what a "Burger" is supposed to be as a player character until it clicked that it's someone from a town.
I like how you've managed to distill things down to d6 rolls - it plays fast and is easy to keep track of. I'm in general not a big fan of having players, not player characters, solve problems, but to be fair, that's just the way that these OSR/BX type games are. Although, it raises the question of stuff like traps - you state that anyone can disarm a trap narratively if they say the right things, but then the Thief also has a specific skill that allows to disarm traps on a roll of 6. There's a couple other dissonances like this in the book in my opinion.
The faction based advancement system is something I've only encountered in a few other games - it's really inspired and I think you've managed to differentiate the factions enough to make it interesting and a worthwhile choice for players.
Combat seems pretty straightforward, but I really wish it wasn't at the end of the book, way after settlement, wilderness, dungeons, underworld and foes. While reading the weapons and armour section, I'd want to know how combat works so I can know what choices to make.
The general sandbox nature of the game is apparent and I'm surprised by how much useful tips and info you've managed to cram into a 49 page book.