The layout of the new responsive modern page

My understanding is right now it is only a single column (unchangeable), but they are working on adding additional layouts in the future.

I'm  not a huge fan of the single column, though i get it from the multiple device perspective, but there are lots of examples like bootstrap out there that can easily demonstrate how to stack and shape multiple columns.

We've been using bootstrap in SharePoint Online for years, so our users are used to the responsive multi-column approach, would love to see this get in place before we start trying to leverage modern pages...