I hear you on the control thing. You mention you are a power user above so my two cents is that likely puts you outside of the user base Mozilla covets. In the last couple years, the words "Firefox" and "power user" went hand-and-hand but I'd wager Mozilla would trade customer bases with Google in a heartbeat.

FWIW, the Developer Edition feels pretty lean and mean. I haven't tried since I am a web developer, but it looks like you can remove most or all of the parts that make it web developer-y if you are so inclined.