Rest & Recovery
Resting is very important in as a way to recuperate lost hit points and replenish your stores of magic for the adventure ahead. These houserules are intended to add some granularity to resting - in the interest of safety or expense, a party may elect to live like vagrants, but this miserable mode of living will do little to sustain them. On the other hand, if they spare no expense in making camp, they will find that they recover remarkably quickly.
At the simplest level, the rate of hit point recovery while resting is 1 so long as a basic standard of comfort is met. In order to regain 1 hit point per night: you must get at least 6 hours of rest, you must have some level of comfort (a bedroll, and a fire/tent if it is cold), you must have eaten something, and you must have a bare minimum of safety (keeping watches of 1 person at a time throughout the night). If any of these basic necessities are not met, you cannot regain even the basic 1 hit point per night, regardless of other factors. The modifiers below can increase the number of hit points gained by resting; note that half-hit points do nothing until they add up to a whole hit point. No matter what modifiers are applied, you can never gain more than one quarter of your hit points in a single night.
Minimum: You have at least 1 person keeping watch throughout the night, or the area is particularly peaceful. +0 hp
Basic: You have multiple people keeping watch, or some form of defense such as an alarm or wall. +0.5 hp
Moderate: You are surrounded by many people, or you are in a place that is very safe, such as an inn. +1 hp
Safe: You are in a safe place, usually indoors, that you know is secure and which you can call home - such as your house or a permanent, guarded inn room. +2 hp
Minimum: You have food. It may not be appetising, but it's enough to feed you. +0 hp
Fresh Food: Your food is not hardtack or iron rations. Perhaps you are eating freshly caught deer, or carrots stolen from a farmer's field. +0.5 hp
Fresh Meal: Not only is your food fresh, but there is variety to it. You're not eating one ingredient, but a stew or a proper dinner. +1 hp
Hearty Meal: Same as fresh meal, but your food has been cooked for you by someone with proper equipment and the Cooking NWP. +1 hp, +0.5 hp for every 3 points the Cooking check is passed by
Minimum: No music. +0 hp
Camp Songs: Songs are being sung or unskilled instrument playing is occurring. +0.5 hp, +1 chance of encounters
Music: Music is being provided by one who knows how to play an instrument or sing with an NWP. +0.5 hp, +0.5 hp for every 3 points the check is passed by, +1 chance of encounters
Chorus: As above, but multiple instruments and multiple players producing loud, rousing song. +1 hp, +0.5 hp for every 3 points the check is passed by, +2 chance of encounters
Minimum: You have a bedroll, and if it is cold you have either a tent or a campfire. +0 hp
Basic: You have a warm place to sleep and are sheltered from the cold and wind. If it is cold, you have a campfire. +0.5 hp
Sheltered: You are sleeping indoors in a bed rather than in a tent or on the floor, and are warm and at least somewhat comfortable. +1 hp
Comfortable: Your sleeping quarters are private and nice, though not the high point of luxury by any means. A comfortable bedroom. +1.5 hp
Extravagant: Silk sheets, feather pillows and stuffed mattresses. You are sleeping in the lap of luxury. +2 hp
As noted in the proficiency description, the Healing proficiency allows an extra 1 hp to be healed each night, even while travelling or engaging in strenuous activity. Complete rest will increase this number to 2 hp per day. If the healer has both the Healing and Herbalism proficienies, remedies made from common herbs can increase this to 3 hp per day. Up to 6 people can be tended in this way per healer.
In some cases, a healer might have access to more extensive medical supplies. Besides the usefulness of such things for treating serious wounds, i.e. broken bones or poisons, they can also help with recovery. The more expensive supplies include honey (for dressings), poultices made from a mixture of herbs mixed with a skilled hand, and so on - coming to a cost of 1 gp per patient per day. A healer tending to a patient in this way can make a Healing NWP check - for every 3 points they pass by, the patient gains an additional 0.5 hp above the baseline, capping out at 3 additional hit points if you pass by 18 or more.