Why would I use your service when I can collect errors with window.onerror and push the data into Google Analytics or Splunk with a couple of lines of javascript?
No, there should be a more stringent review of the permissions apps request. The dangerous ones should be marked in red and you should approve each one individually.
Apart from Scroll Lock and Pause, I don't see anything else that I'd want to be gone. Caps Lock - maybe, but many people use it. Windows keys annoy the hell out of me, but many people use them too.
It doesn't matter. Developers almost never develop/test in an environment that mimics production - multiple load balancers, multiple app servers, multiple database servers, failover to a second data center, etc.
If your dev environment is not different from prod, you're either insanely rich of your server setup is trivial.