Is there a possibility to delay the workflow so that no mail is sent on a certain date (e.g. because it is a public holiday)?
Alternatively, it would be helpful if you could choose working days instead of always and certain weekdays.
There is no way to set local holidays to pause workflows. What I have seen many companies do is just pause all existing workflows leading into major holidays and then unpause them after they are complete.
As what you are posting are also ideas to improve Hubspot, I would recommend making a second post there so your ideas can be voted on.
https://community.hubspot.com/t5/custom/page/page-id/ideaslandingpage