if you're running this in production, swap out those json state files for Redis with SETNX and TTL, because otherwise you're gonna get absolutely hammered by alert spam and race conditions once you scale up. also actually test your geos against real targets you actually care about, not just some random IP checker, because 2026 taught us that the nightmare scenario is regional blackouts where your global monitoring says everything's fine but a specific country's pool is completely toast. So split your timeouts into connect and read separately so you can actually tell if it's a gateway choking or your exit nodes getting wrecked. And start tracking cost-per-successful-request because that's how you catch a pool quietly degrading before it face-plants spectacularly