I have a few more suggestions, some of them have definitely been made before but I think they would be a great addition:
Once NPCs are more fleshed out, be able to use the environment as cover in a gunfight.
Crouching/Prone stance to reduce visibility and recoil, and increase accuracy.
Bracing your weapon against walls, windows and other obstacles.
Climbing/Hurdling over cars
"Set and forget" for crafting where it makes sense (no needing to babysit your jerky)
Giving NPC followers complex orders
Scavenge and RTB
Guard a location
Skirmish/Attack enemy encampments
Telescopic mirror, to check around corners without exposing yourself (great to check for those damn turrets in the labs)
Modding melee weapons
Add more weight to the head
Electrify with batteries and wire
Add fire (like the shishkabob from Fallout)
Reduce weight (can make it less sturdy at lower skills)
Desert Eagles and .50AE
The Junk Jet (From FO4)
Crude bandages (rags and alcohol) that only last for a few hours before they dry out
Saline solution able to be used to irrigate wounds (deep bite wounds)