about vacations:
school summer vacations are historically so that kids could work in the fields. Winter vacations – to celebrate saturnalia and such.
Jews in Bavel indeed had vacations twice a year between harvests – so that they could go to yeshiva to learn.
Netziv went to lakes in Lita when doctors insisted that his health requires it. He ran away on a second day back to yeshiva.
R Salanter took vacations seriously: when he was told that his health requires visits to a spa, he was noticed there re-reading doctor’s instructions to make sure to do exercises as prescribed and at prescribed times, and also eating non-pas-yisroel bread because someone donated money to help him improve his health, not his chumros.