What are your favorite outdoor RPE-based workouts?

My fancy bike is in the shop for a tune-up, and I am taking a couple unstructured weeks since I recently finished my first century (woohoo!).

What are your favorite workouts to do outside without a power meter? What do you think works well about them?

I can’t offer any direct workout suggestions, however if you’re riding unstructured then why not just ride for fun? It sounds like a good opportunity for such