I know that there are many ways to fix the class system, but I disagree with scraping the old. First off the Armory system is what sets this game apart from other games, and any changes to it should be focused on the armory system. they shouldn't focus on Jobs. Rather try to fix & expand the Armory system. So while changes are needed I don't believe they should just start anew. Anyways here is a concept that I thought about.

Favor System
The Favor system is very similar to the FFXI way of Blue mage getting traits by equipping skills. What it does is by equipping the appropriate skill to the appropriate class you gain a trait. However unlike the FFXI system you would basically get a trait for every Skill instead of having to set many skills to gain a certain trait. here how my concept would work with Conjurer. (The trait is automatically equipped with the skill.)

Conjurer
Aero (Favor Trait:Increases Affinity with Wind based magic.)
Fire (Favor Trait:Increases Affinity with Fire based magic.)
Water(Favor Trait:Increases Affinity with Water based magic.)
Stone(Favor Trait:Increases Affinity with Earth based magic.)
Blizzard(Favor Trait:Increases Affinity with Ice based magic.)
Thunder(Favor Trait:Increases Affinity with Lightning based magic.)
Trance Chant (Favor Trait:Increases MACC by 5)
Cure (Favor Trait:Increases MND by 5)
Stoneskin (Favor Trait:Increases VIT by 5)
Repose (Favor Trait:Increases PIE by 5)
Shock Spikes (Favor Trait:Causes Lightning based damage to heal you)
Profundity (Favor Trait:Increases MATK by 5)
Radiance (Favor Trait:Increases Max MP by 5%)
Burn (Favor Trait:ATK +5)
etc..... you get the point.