I'd suggest forgetting about UGC for now and focusing on routes that have a real identity behind them. When my wife and I visited Japan recently, we watched several travel vloggers to see how each one planned their exploration of different neighborhoods. We picked the ones whose style resonated with us and tried to replicate their approach.
Imagine if, for a given area in a city, you could offer an exploration route tied to a specific travel creator and how they actually did it. It would feel more authentic. There's a personality behind the route, not just an algorithm. You could pull from travel videos on YouTube, use AI to extract the route and key stops, and then attribute it: "This route was done by [vlogger]." That gives you the authenticity of UGC but with real curation.
It's also a practical way to scale up your route library without burning a hole through your pocket.