Thanks! Good Questions
1. We haven't enabled BroadcastChannel in the Edge Runtime. Mainly because we haven't found good use cases for it within Edge Functions (it does make sense as a way to subscribe within a browser client, but not sure how it fits with async/short-lived nature of Edge Functions). Curious about how you plan to use BroadcastChannel in Edge Functions?
2. As I've mentioned in the blog post Edge Runtime allows you to tweak the duration and memory available for an Edge Function (check the examples/main/index.ts in the repo too). Personally, I use this option to debug timeouts and memory issues on Edge Functions. We also plan to introduce better ways to profile your Edge Functions in the future.