After working with Customizer a bit I really dont like it. I find it somewhat convoluted. And that is with just minimal stuff in the Customizer. Been working with some free themes I found at wp.com, adding more controllers and what not. Its hard to get an overview, its hell to combine it with responsive behaviors, there is a lot of steps just for adding a minor color change. You write the PHP code for the controller, then you need to write the controller for the JS part, then you need to write the code for the actually printing of the CSS code on the frontend. Also some parts does not seem to work with HHVM. Image controller generates ArrayAccess exception (when I try it out atleast). From my point of view the Customizer is "broken" from the ground up. I werent claustrofobic before but after making theme changes through the customizer I want to screem and run around on the plains waving my hands in the air.