inconver

You can add new sidebars in the admin panel and edit them.
You can add new types of widgets and edit them. 
Also, you can add custom fields for new types of widgets. 
And you can create a unique template for each new type of widget.
Video tutorial: <a href="http://inconver.com/wui/" rel="nofollow ugc">http://inconver.com/wui/</a>

WUI: Widgets User Interface

Plugin for creating new sidebars for the site and new types of widgets with the custom fields

Trevor Anderson

Split sidebars and widget areas into responsive columns.
Two simple widgets are provided, “Layout: New Column” and “Layout: New Column on New Row”.
Simply place these in your widget area where you’d like to create a new column (split) or new row of columns.
Gutter size and responsive collapse options are available in the Customizer -> Widget Columns panel.

Tuxedo Responsive Widget Columns

Just tested this plugin, and it works exactly as I hoped for. I can now have complex layouts in any widget areas. 
Of course it's best used for horizontal widget areas like footers, etc...



Works perfectly!

Split sidebars and widget areas into responsive columns.

WUI: Widgets User Interface vs Tuxedo Responsive Widget Columns