Using the paged layout reduces the amount of width we have to show the map in.

Also your caption patch only supports plain text at the moment. If you converted that to wikitext, you would still need Parsoid support for VE to be able to edit it as rich text.

In T143418#2568367, @Esanders wrote:

Using the paged layout reduces the amount of width we have to show the map in.

The current side menu indeed leaves less room for displaying the map.
We can make it a two-step process, without the menu. I'll update the mocks.

In T143418#2568380, @Esanders wrote:

Also your caption patch only supports plain text at the moment. If you converted that to wikitext, you would still need Parsoid support for VE to be able to edit it as rich text.

Good point, we should support wikitext in captions.
/cc @MaxSem

Here are two mockups illustrating a two-step process, allowing more space for editing the map. I also added alignment settings.

Hmm, is this task being done by anyone? This is clearly "great to have", but it doesn't look like a major blocker for <mapframe>.