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Several ways to use columns. They aren't necessarily difficult to construct, but they complicate views on various devices. I see this as an advanced feature, not recommended for most users.
Macros
Page Tree. Simply lists pages in space. I strongly recommend this for the home page for each space. Indeed, we might make it the only allowable editable content on each space's home page, other than perhaps a welcome message. We should have this despite a page tree existing in teh sidebar and the "child pages" list below, because those are not visible in mobile.