Are we playing the same game?
PA is supposed to be the ultimate Fallout armor. It's been better than every other option in every category except weight since the very beginning. Fallout 3 broke this.
Fallout: New Vegas makes PA far stronger and more worthwhile that Fallout 3, but even then it is but a shadow of the old PA thanks to DT bleedthrough and the prevalence of lighter armors. Lighter armors are stronger in New Vegas because they allow a character to move faster than PA and with chems & perks, can easily provide more benefits including defense.
As for weapons...every weapon can be game-breaking if used right, with a character build dedicated to supporting it. That said, here are what I see as the ultimate weapons in each category, minus uniques and DLCs:
Guns: Minigun ~ AMR ~ Brush Gun ~ Ranger Sequoia ~ 12.7mm SMG ~ Marksman Carbine ~ Sniper Rifle.
Energy Weapons: Tesla Cannon ~ Plasma Defender ~ Plasma Caster ~ Gatling Laser ~ Heavy Incinerator ~ Gauss Rifle ~ Flamer.
Explosives: Missile Launcher ~ Grenade MachineGun ~ Fat Man ~ Plasma Grenade ~ Grenade Rifle.
Melee Weapons: Super Sledge ~ Ripper ~ Chainsaw ~ Thermic Lance ~ Shishkebab ~ Combat Knife ~ Throwing Spear.
Unarmed: Displacer Glove ~ Ballistic Fist ~ Zap Glove ~ Mantis Gauntlet.
That's quite a bit of variation between brute power vs rate of fire vs weight vs critical chance vs critical damage vs Strength/skill requirements...ultimate power of weapon depends mostly on the character.
If the most powerful weapon depends on the character, than so does the second and third most powerful weapon, and the difference between them. Therefore, there is plenty of power range between weapons between characters.
I would have liked to see the AK-112 Assault Rifle, but I think the Assault Carbine is that.
-Nukeknockout