So, I had this idea. I want to build a Courier who aspires to become a Brotherhood of Steel Paladin. Paladins are adept at using ALL weaponry, Energy Weapons, Guns, Explosives, Melee Weapons, and Unarmed. I won't have the benefit of Knights and Scribes to maintain my equipment, so I need decent repair and science skills. I also would like to be strong enough to use any weapon I may come across, although not necessarily for level 1. I have all 3 DLCs, OWB gives us +2 Strength which helps a lot. How do I create a character who represents all 3 of the Brotherhood's Classes?

Equipment I want to use:

Guns:
Anti-Materiel Rifle
C757 Avenger Minigun

Energy Weapons:
Laser Pistol (for a very short while, or as a back up)
Gauss Rifle
Laser Rifle
LAER (maybe)
Tesla Cannon
Flamer
Gatling Laser

Melee Weapons:
Oh, Baby
Chainsaw/Thermic Lance (it matters not)

Unarmed:
Power Fist
Pushy

Explosives:
Annabelle
Grenades of all flavors
Mercy

So, yeah. Kind of a tall order.

Which PA are you going to use?
You would want Energy Weapons, Science, and either Repair (Scribe), Medicine (Paladin), or Survival (Scout) as tag skills

High PER in all cases
If a Paladin, high STR as well
If a Scribe, high INT
If a Scout, high END

Outfit

Power Armor if a Paladin
Recon Armor if a Scout
Robe (Bright Follower will do) if a Scribe

Weapons

Heavy weapons for Paladin only
Gauss Rifle can be used by all
Laser Rifle and Laser RCW can also be used by all
Pistols (incl Plasma Defender) mostly for non-Paladins

You can use BoS T-51b for Paladins and either Elijah's Robe or a Scribe Robe (PC only, must be consoled in) for a Scribe, but be aware that those are faction armors and NCR or Legion troops who spot you wearing one will shoot on sight.

Obviously you would want to do the BoS quests, and I would recommend going Independent for the main quest unless you decide that it's in the BoS's best interests to ally with the NCR. Not sure if you would want to recruit Veronica or not, as she's something of an outcast, so I'll leave that for those who have done her quests to answer.

T51-b, was my armor desire. I want to use all of the above weapons (not all at once). I was planning on recruiting Veronica and working with NCR. I'm progressive.

Well then try starting with this:

Strentgh 6
Perception 6
Endurance 6
Charsima 1
Intelligence 9
Agilty 6
Luck 6

Raise Endurance with Intense training perk to be able to get all the implants.
Tag skills:Energy weapons,Repair,Science
Traits:Skilled and Trigger Disiplne

Alright, I'll see how this works out