In Unturned I the only things that can happen to you is breaking your leg or bleeding out. This is cool, but it isn’t cool enough. In Unturned long-range PvP can last forever if a player gets shot, hides, and just spams meds, which is not very realistic.
My suggestion incorporates some things I posted or read on the Zombie Accuracy post:
Players should be able to injure different body parts during combat, and there should be different types of medicines, splints, and whatever else for each bodypart. The injury can be a simple injury, which causes a loss of accuracy/speed/etc depending on the bodypart, and it should go to the extent of losing bodyparts (very hard to heal), which can make pvp more fun. Losing a bodypart should only exist when being hit by very large caliber weapons, and the only way to fix it is to quickly apply heat, seal the wound, etc. It’d be cool if they add prosthetic limbs also, some of which may have an advantage in pvp (but some other disadvantages in general, such as reduced ability to craft).
In terms of the more minor injuries, you should be able to apply a splint or whatever else, which heals the bodypart over time.