Here are some house rules I use in my game that people might find useful:
Persistent fire damage: Instead of auto-ending on an agi+athletics with difficulty equal to turns of ongoing, test is difficulty 1 and reduces ongoing by one turn. For every 1AP spent on a success, reduce it by another turn. Similar rules apply for other types of ongoing damage or affects that can be remvoed with a test as a major action.
Non-Lethal quality and attacks: I have added a new weapon quality called “non-lethal”. Please add this quality to basic unarmed attacks (ones without any “unarmed” weapons such as knuckles, etc.) , as well as to the “boxing glove” unarmed attack. Also add it to attacks with the “stun baton” melee weapon. Weapons that have this quality can be used to make non-lethal attacks without penalty. Note that the base (unmodded) boxing gloves can only make non-lethal attacks. You must declare an attack as non-lethal before making the attack. Non-lethal attacks reduce HP as normal, but if they reduce a target to 0HP, they instead reduce it to 1HP and they are knocked unconscious. At the beginning of each of the target’s turns it can make an end+survival check to wake up, with the difficulty being 1+number of injuries. If the target was also stunned when knocked out (for instance from a head injury, including the attack that knocked them out, or from a stun weapon affect, again including the attack that knocked them out, the difficulty is increased by 1 (in addition to the 1 from the injury if it were due to a head injury), until the stun effect ends. If a stimpack or first aid is applied to treat an injury or restore HP on the target, you may spend 1AP to also wake up the unconscious target, otherwise you can instead do a first aid check to wake them up (difficulty 0+number of injuries+1 if they are stunned), or use a stimpack to only wake them up.
Addiction: Addictions will be treated as diseases (except they do not spread), and have a disease duration of 4 if they have an addiction rating of 1, 2 if they have an addiction rating of 2, or 1 if they have an addiction rating of 3 (except for ultra jet, which has infinite duration). The addiction penalties do not go away until the addiction is completely treated down to 0 duration. If you take the drug or any related drug (jet fuel for jet, for example) before the duration has been reduced to 0, it goes back up to its original duration.
Swarm rules: NPCs that are identical and attacking with the same weapon from the same distance can act as a swarm up to 15 “small” enemies, 8 normal enemies or 3 “big” creatures can be in a swarm. Swarming creatures attack as 1 and get +1d20 for each attacking creature beyond the first to a max of 4d20. For “small” creatures, each additional creature adds +1CD to the damage, for normal creatures it is +2CD, and for “big” creatures it si +3CD. For each creature beyond the first in a swarm, the critical damage threshold is increased by 1 (so 2 creatures would need to deal 6 damage to cause an injury, 3 would need 7 damage, etc.).
Terrifying Presence Perk: You can take this perk if you have greater than 5 but lower than 8 CHA. If you do, it only applies if you are a super mutant or wearing power armor.