-Comfortable
-Detachable cable
-Perfectly open or perfectly isolating, depending on user preference
-Does not need a specialized amplifier (and can function portably)
-Really comfortable
-Won't empty your bank account several times over
-Soundstage and imaging so good it's like you're there
-Maximum transparency, clarity, and effortlessness of sound
-Did I mention comfort yet?
I don't think my ideal headphone will ever exist...but for now, I've found something as close as I can realistically expect in the Stax Lambda line.