A Tactics approach to Class/Job system

It was mentioned in another thread that instead of having the classes changed into jobs we're familiar with, the jobs are titles instead that confer certain bonuses into certain aspects of playing. These titles would be available at certain ranks of certain classes, so they aren't immediately available. A good idea, but some people don't feel like playing 4 different classes to ridiculous extents in order to unlock their favorite job.

My idea is to instead have it based on the number of abilities of certain classes set, as well as the type of abilities set, somewhat similar to how your combat title worked in Fable. If you wish to play warrior, equip 3 MRD abilities; paladin, 3 Disciples of War and 2 astral aligned Disciple of Magic abilities; black mage, any combination of 3 elemental or umbral alignment offensive spell abilities. This way, not only can you restrict certain jobs from players too low to access them through the fact that they don't have enough action points, but you can also allow for the same job to access different roles depending on which class it's played on. A paladin played on THM would still be a holy warrior, only instead of using blessed weapons, they call down the power of the gods to smite their foes. A red mage on GLA would still be capable of enfeebling and nuking, albeit it's weaker than their CON counterparts, but their main strength lies in their elemental blades. In addition, equipping more abilities in alignment with your jobs will give additional bonuses. Going to 6 MRD abilities will give additional offensive power to warriors, while adding GLA abilities will boost defensive capabilities, and PUG will give more evasion capabilities.

If simply cross-classed abilities don't make your role feel special enough, then make certain abilities available to you only when you activate a certain title on a certain class. A Dark Knight on a MRD or GLA would be able to choose to equip Blood Weapon too emphasize their tanking capabilities, while on ARC or LNC they can choose Soul Eater, and on CON or THM they have Dark Seal to enhance their casting. Or make certain titles specific to certain disciplines; after all, having a GLA go white mage would be rather awkward with how the play style goes.

This is just an idea though, and like all ideas, there are good points and bad points to it. Feel free to criticize it, as I know how blind I can be to the weaknesses to my own ideas.