The number 12 should be the last 1-digit number. Not 9.

12 is divisible by 1, 2, 3, 4, and 6.

9 is divisible by only 1, 3....

Time is set on a 12-hour clock, so it would make more sense that way, too.

Decimals would be easier to chop into thirds. (As opposed to the 0.333333 bullchit we have now)

13 is a prime number, which makes it a better candidate for moving into double digit territory over the number 10, which is not a prime number.