Personally, I would go for naming them after the twelve largest moons in the solar system, since they were originally (and still are in many cultures) based on the lunar cycles, giving the months Ganymede, Titan, Callisto, etc.
What would you rename the months?
edit: Simply using the numbers is already a thing (see, for example, 2026-01-01. January is represented as month 1), and reordering the existing month names would be a real headache, as it would be difficult to tell whether you are reading a date using the old or new naming scheme.


No love for the French Republican Calendar months?
People who know their Latin roots might know what these months are named after, but here’s a guide:
Today (2026-03-23 UTC) would be the 23rd of Germinal, 2026 CE.
Wait, I thought the French Republican Calendar had 10 months only?