Using Linux Mint 17 Cinnamon with different themes, I see that few elements are changing with the theme, while most remain unchanged, especially the general background of windows and applications, which remain grey.
Icons and windows decorations are changeable but not through the theme.
The only thing that really changes is the panel and its applets.
Firefox is not at all affected by system themes and even Firefox themes cannot change the colour too much.
The file managers are not affected by the change of theme. Not at all. Even the minty selection is unaffected. There is no flatness and no transparency for file manager windows and for windows in general. The grey is there to stay.
The general look is elegant but the lack of customization makes one think to the mac file manager than to a Linux environment.
While windows decorations can be changed separately, the space below them stays grey no matter the theme, so for the sake of consistency one is tempted to keep a default grey too.
Is this a general Cinnamon aspect or limited to Mint?
Or maybe I miss something here?