World Building
GM does seem really great.
So, the idea for the setting seems to be focused around a specific town. Hmmm. I don't know if I like the 'something drastic happened and the town where everyone is was cut off from everything and its only just exploring a world it knows nothing about'...
Maybe this is more like a frontier town on the coast of a new continent. Maybe it's been growing for 50 years or so, and it's kind of a foothold on this continent from peoples of another, attracting the curious of all walks who want to seek freedoms or fortune and opportunity, to discover the wonders of magic and such that this new land offers.
On one hand, this might mean that the 'magical loot' here is less expansive, or maybe takes different forms. But there's also the possibility of past adventurers having fallen and lost things. Maybe the 'magical loot' takes different forms, or maybe a lot of it is crafted locally. Maybe there are other settlements too, along the coast, some further inland. Maybe 50 years isn't enough wind-up time, maybe it's longer?
Might also be a way to work in the potential for local peoples, too, draw on real-world circumstances as an inspiration for conflicts and such between locals and the arrivals. It wouldn't even need to be a case of 'advanced vs tribal' - the locals could actually have castles towns, too, but we're starting from a perspective of people new to the area, but we can fill out the stuff that's out there as we go?
Just speculating a variant that still allows the world to feel explorable without feeling 'rootless'?