I just created a Github pull request for Home Assistant to customize the sizes of the Lovelace maps almost arbitrarily: The change allows columns and rows smaller than the minimum values specified in the grid_options settings. Background: Creating a dashboard for mobile device or dashboards has become quite a challenge as some cards are much too large.

The default for the entity map is 6 columns and 2 rows:

With the change, maps could be customized much more flexibly:

YAML still uses the default parameters for the grid options, but these can be smaller than the defined minimum sizes:

grid_options:
  columns: 4
  rows: 1.5

This pull request should leave the GUI limits as they are, but allow smaller sizes to be specified in YAML. This allows the layout to be dimensioned more flexibly and creates new possibilities in combination with a theme.