A Warrior is actually what you need, WARs are not boring and they are actually very very strong. They are stronger than DRKs up til 66ish when they learn Spinning Slash and can still keep on to par with them.

A DRK is a pure offensive, there are almost no defensive abilities for him unless he subs WAR for Defender and a PLD is the same unless he uses Berserk and even then none of them would be even near each other. Adv jobs are usually more specialized. WARs are not.

WAR/NIN can be a damage dealer post 48, and then tank semi well.

WAR/MNK is an excellent tank up til 60. PLDish

WAR/THF is a great skillchain closer especially with Raging Rush WS or with Rampage Axe WS.

Seriously the closest one is WAR, they even have the Break ATtacks with GAxe(which they are A+ in). and WAR/NIN at 74 can tank even the worst of things while doing great damage.

WAR:
Provoke
Berserk
Defender
Agressor
Warcry
Def Bonus
Atk Bonus
Virus resist
Double Attack
Can sub THF NIN MNK and most other subs without much penalty..but the first three are more preffered

PLD:
Cure Spells
Enhance Spells
Divine Spells
Sentinel(DEF)
Shield Bash
Rampart
Cover
DEF Bonus x 3
Holy Circle
Undead Killer(intimidates undead..not that great)
Subs mostly WAR

DRK:
Weapon Bash
Dark / Elemental spells
Soul Eater
Last Resort
ATK Bonus x 3
Arcana Circle
Arcana Killer
Subs WAR and THF

Basically if you want to group and compare these two, its from DEF to ATK

PLD - WAR - DRK...with WAR not being too bad with either as long as you equip yourself right for the situation..they can nearly be as good as PLD and DRK.

Lets just say that, if you wanna do it all for melee jobs..go WAR for the best of both DEF and ATK.