WTH setting relative sizes of cards within a horizontal card

Would be great to be able to set the size of horizontal cards as not all cards deserve equal sizing. Some work better with smaller space.

For example, specifying sizing either in percentages or as fractions:

type: horizontal-stack
size:
  - 2/3
  - 1/3
cards:
  - type: mini-graph
    entity: sensor.aqi
  - type: bar-card
    entity: sensor.allergens

Here is a different visual example of varying sizes within a horizontal card.

A lot of this might change when the ‘grid’ is done being developed.