I’d personally prefer 12 months with 30 days each, a 6-day week (makes for even rotations in shifts, 4 on 2 off), and an inter-calary week of 5 to 6 days at the new year.
If we’re going for broke on this I’d also want to convert to the dozenal system over decimal, as 12 is more easily divisible by smaller numbers which means easier division for numbers we use more often (like 3 or 4), which means that ¼ would be 0.3 and ⅓ would be 0.4.