An additional point on (2). One thing Firebug does right that neither chrome nor the built in tools does is show a decoded version of the JSON for both the send and receive sides of a connection. I love being able to click the request in the console and drill down into the JSON tree.
If you're dead set on replacing firebug with the built in tools, they need this feature!
If you're dead set on replacing firebug with the built in tools, they need this feature!