So, the show/hide feature seems to be the one really interesting thing to me. We're both vimmers and it sounds like we have similar workflows. What's killing me right now, is that coming from Debian I always had 5 desktops setup on Alt+1-5. I've got the same thing on Command+1-5 now, but if I force Terminal.app to fullscreen in OSX in the Desktop 1 spot, it's no longer available via Alt+1, since it spins up it's own, new desktop called 'Terminal'. It kills me.
In your post, are you saying that you can have a fullscreen iTerm2 window transposable to any of your desktops with the show/hide hotkey? Because this would push me over the fence.
BTW, I dig the CSS triangle inversions you're using for your ribbon up top.