Really interesting migration story. Moving validation and lightweight logic to the edge can make a huge difference in user experience, especially when most requests don’t actually need to travel all the way back to the origin. The latency drop you mentioned (200ms → ~50ms) is a solid improvement.
I also agree with your point about state management. A lot of developers underestimate how different things become when you move compute closer to users. Sessions, caching strategy, and data validation all need to be rethought.
Latency like this can even affect how tools and web utilities perform globally. I was recently reading about how response time impacts user engagement across different regions here: https://myagecalculate.com/
Curious if you also noticed any impact on API error rates or just bounce rate after the migration?