Open Radar

 
The improved management of multiple monitors is awesome. I can finally use spaces with my setup. 

But I find the additional menu bar confusing as it is in the current version, because it's not always immediately clear what makes a secondary menu bar active. Technically of course it is, but it's still an additional mechanism I have to bear in mind, especially when I use keyboard shortcuts to activate Spotlight, Notification Center or other apps and they pop up on my secondary screen, when I would expect them to use the main one.

I propose to make the main menu bar always the active one. Let the menu bar (and Dock) on secondary monitors only slide in when summoned with the mouse at the upper or lower edge of the screen. Make them slide out automatically when the mouse moves away! This would still allow quick access to the menu bar and Dock on all monitors, but the notion of having a "main" monitor would make sense again, because the Dock and menu bar would stick to that one, and only move/appear temporarily on the other ones, when needed.

Alternatively, you could make the additional menu bar (and the Dock separately) optional. The Mission Control option "Displays use separate spaces" removes the menu bar, but also (as it says) reverts to the Mountain Lion style multi monitor handling of spaces. It would be nice to have these as separate options.