Firebase Team AMAView other answers to this thread
What is firebase's worst tech debt or design decision that you most regret in the backend?
With 18 products that's so hard to say! I can definitely say we wish some of our earlier services were deployed more globally (like Cloud Firestore). So many developers want Realtime Database or Firebase Hosting to be served from near where they live or where their users live. But we're definitely looking at ways to solve that!