Andrew Boon
Width of each column will be controlled by template. We see it's a more logical way to handle it - too many custom templates get broken with incorrect column-width choice.

Multiple-blocks per row would complicate the system and interface and code. We don't want to go that way in D8. We want it functional and simple and fast.

As a workaround you could use a "content only" block and HTML to mimic multiple blocks within one row manually, if absolutely needed. I don't' see much use see more for this though.
Oh nice then, but it will be a good idea if you also create a system for template designers so they can have adjustable values and settings in admin panel for each template (like the simple wordpress template settings).
Custom text fields, dropdown menus, sliders, image uploaders (for logo and slide shows), variables, template css edit in admin panel etc. So you can control for example the copyright text, some footer links (social links) or as you said the number of columns and their width, different see more javascript settings etc..
Andrew Boon
We got this. Every template has its own settings page in studio, where
Developers can add anything they want.
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