The calendar we use is bollox. There should be a calendar with a set number of days per month. E.g. 13 months with 4 weeks per month, so standard 28 day months and account for the lead year at the end of every fourth year.
That way the days would be fixed to dates of the month. Every 1st, 8th, 15th and 22nd of each month would be the same day of the week every month for 4 years in a row. So much simpler and so much easier to plan into the future.
P.S. Julius Caesar did well to come up with the current calendar when he did. Things had gone to sh1t in Rome when he took over, to the extent that they had lost track of the date and were about 40 days out. But i think we could do a lot better now and the standardised calendar would be much better