Why not define the benefits and requirements, then let players do these whenever they want? Whatever makes sense for the narrative.
• 5-minute “Breather” (Short Rest)
• 1-hour “Break”
• 6-hour “Sleep” (Extended Rest)
Make the 1-hour Break sufficiently useful to avoid the need for Sleep. Thus prevent the 3e “5-minute workday”, or the 4e “35-minute workday”.
Use these same time standards for rituals and spellbooks.
• 5-minute “Breather” (Short Rest)
• 1-hour “Break”
• 6-hour “Sleep” (Extended Rest)
Make the 1-hour Break sufficiently useful to avoid the need for Sleep. Thus prevent the 3e “5-minute workday”, or the 4e “35-minute workday”.
Use these same time standards for rituals and spellbooks.