The healer is a vital part of any campaign. A party featuring a well rounded healer will make it further because of them. Outlined below will be several different ways to create, play, and advance your healer in the post nuclear world.
Character Concept and Creation
Character concept is a very stressed idea in any RPG. A very important aspect of your character is how he will be Role Played. This should be decided well before you enter further creation. A couple prime examples are the doctor. Was he trained pre-war or in the vault as a doctor? Did he stumble across books, equipment, or others to teach him after the vaults opened? Is he a ghoul who lost his body but not his mind, and is still able to perform surgery? Or is your character a nut case witch doctor. Not so much going on upstairs but he gets the job done. Remember that avoiding comedy isn't always a good idea. Consider the Fallout video game series, they were full of comedy and it made it more enjoyable. So if you think a goofy witch doctor will add laughter to the night while keeping the party alive, it may work for you.
The race of your character should be logical. While I said a tweaker shouldn't be a min-maxed freak, he should be able to do his job. The human is the very base of a tweaker character. The human can be used in so many ways to get the job done. In the case of the doctor the human can handle himself. The ghoul is also a great choice, featuring high intelligence and perception. A ghoul can make a fine, yet ugly, doctor.
In the case of the doctor, traits can be interesting to pick, mainly due to the fact that doctors don't have many traits aimed for them. Of course Good natured is a very good choice. In a sticky combat situation the doctor isn't likely to be wielding a .44 along side injured, fallen, or dying comrades. For this reason the 10% lost in combat skills isn't a big deal compared to the 20% increase in first aid and doctor. Another good choice for a trait would be bloody mess. If you have a creative GM a patient who died could make for a very interesting mental image. No other trait is too practical or needed for doctors. Although some players may enjoy another for personal or role playing reasons.
The statistics of a doctor are pretty easy to pick out. You should have Above average to Very good intelligence and perception. This will put your first aid and doctor at a high advantage. For this reason the ghoul is a good choice for a doctor as both can be stretched very high. You may also want to have decent endurance and strength; hauling equipment isn't easy, and you want to be able to stand up to some abuse if you are healing the 330 lb mutant you room with mid-combat.
Skills you tag for doctor should revolve around healing, obviously. So first aid and doctor are a must. Others to consider are small guns for protection, pilot so the driver for the team isn't the meat shield, or science for medical research reasons.
The equipment of a doctor should include items such as first aid kits, stimpacks, rad-away, surgical kits, or any other medicine or kit for healing, fixing or otherwise saving lives. Some kind of personal fire arm and ammo is a must in the post nuclear world. Also consider some type of light armor. Or a lab coat. If you have that witch doctor, maybe a large red robe and tribal facial tattoo's.
Character development is just as crucial as the initial creation. and you must follow with your concept as much as possible throughout the game. Sometimes it might be tempting to pick up the sniper feat with your 12th level doctor, but ask yourself, will that save lives?
When you receive skill points for levelling, consider spending them on things you KNOW you will need. With the doctor it is crucial to spend some points on first aid and doctor. Self defense, bartering, and speech are also part of the doctors day. Frankly a group of slavers are likely to shoot the doc down when he tries to heal the best gunslinger in the party, medical supplies are not free, and doctors are looked at in positive light in most of the world. A doctor talking could mean something in a Role Playing scenario.
Perks should be used wisely. Like any character perks can be what turns you from OK to great. Suddenly you heal more damage or you can fly! What isn't great about that?