You’re definitely right that people can agree on the length of day and year regardless of where they live. This way, there’s no urgent need to change that part of the system.
Since 365ish isn’t a number you can neatly divide with anything, I suggest we just pick some number you like, and then add a leap day when needed. So, let’s say you want to divide the year into 10 decimal months, so let’s call them “donths”. Each donth has exactly 36 days, which means that at the end of the year you still have 5ish days left. It’s not exactly 5, because astrnomy, but don’t worry about it. Then you’ll just lump all the remaining bonus days into an extra donth and you’re done. The length of the first 10 donths is always constant and the length of the leftover extra donth at the end of the year is whatever it happens to be. You could make those days a national holiday when people just wait for the new year to start or whatever.
You’re definitely right that people can agree on the length of day and year regardless of where they live. This way, there’s no urgent need to change that part of the system.
Since 365ish isn’t a number you can neatly divide with anything, I suggest we just pick some number you like, and then add a leap day when needed. So, let’s say you want to divide the year into 10 decimal months, so let’s call them “donths”. Each donth has exactly 36 days, which means that at the end of the year you still have 5ish days left. It’s not exactly 5, because astrnomy, but don’t worry about it. Then you’ll just lump all the remaining bonus days into an extra donth and you’re done. The length of the first 10 donths is always constant and the length of the leftover extra donth at the end of the year is whatever it happens to be. You could make those days a national holiday when people just wait for the new year to start or whatever.