Why are you calling this the most customizable version when you've taken away customization options?
I used to be able to move the back, forward, refresh, and stop (and make them separate buttons as well). With this version, they're immovable, and you're some how saying this is more customizable.
Alle svar (1)
For the first time, starting in Firefox 29, the menu is customizable, and there is a right-click option to easily move items between the menu and the main navigation toolbar. But you are correct that some previously detachable parts of the address bar are no longer detachable, and the tab bar can't be moved below the navigation toolbar through the customize feature.
I don't know how to score that mix of gains and losses, but really, this support forum is aimed at making the current release of Firefox work for you. Did you find a solution, such as the Classic Theme Restorer extension, or are you still in search of one?