The main problem with having class changing as an option is balancing. Look at bravely default (haven't played the second game yet so I don't know if this is different in there), there are like two or three really broken combinations that just make the game a walk in the park.
Oh yes. Dual-shielding Paladins with Ninja secondary Job to force the enemies to attack only them and healers that heal the whole group for 9999 with spread-Cura. :/
Yes, games with job systems could be narratively weaker than games with fixed classes, because characters may feel too similar to each other / generic. That was one reason why I asked the question about character-specific skills or giving them more pronounced statistical biases, so that while they may be used in any class, they are more useful in certain ones, differentiating them and giving them more character. Distinct personality quirks would also help.
Actually, the original idea for my game addressed this(it has since changed drastically, to the point it's an entirely new game. However I am still planning on making the original concept at a later date, lol). The game had 4 characters and 16 classes. Each character had access to 6 to 8 classes (One character could access 6, one had access to 8, and the other two had access to 7 each). The classes were split into "Archetypes" or Arcane, Primal, Divine, and Martial, as well as into "Roles" of Damage, Defender, Healer, and Support. Each of the characters was assigned one Archetype and Role (Arcane/Damage, Primal/Defender, Divine/Healer, and Martial/Support). The Arcane, Primal, and Divine Archetypes all had one class for each Archetype, while the Martial Archetype had two Damage classes but no Healer. So, for example, the Arcane/Damage character had access to the four Arcane classes and the four Damage classes outside the Arcane Archetype.
However, despite the fact that there was a large amount of overlap in the true classes, each character had their own unique flavor for their specific class. For example, the Arcane/Defender class had a different flavor for the Arcane/Damage character than it did for the Primal/Defender character. The Tank character's version was more of a combination of Arcane and Primal for purposes of flavor. In the case of this class, the Arcane/Damage character took on the forms of Demons (Demonologist) to mitigate damage, while the Primal/Defender character called on animal spirits to aid them in doing the same (Animist). On the same hand, the Arcane/Damage character's Martial/Damage classes were more like spellswords than the Martial/Support character's versions (one was based off a staff-wielder like certain types of Monks, while the other was more like a Rogue).
While the Berserkers class is based around applying a "Bleed" effect. When the enemy is under the bleed effect, the berserker gained stat bonuses, crit%+, etc. so your goal with the class is to stack bleed and have high damage output.
The berserker is also limited to light armor and uses axes.
Hehe- I've got a Barbarian-type class, too, though revolving around a different mechanic. Rather than basing it around Bleed (one of my other classes already fits that), my Barbarin class, called the Soulrager, focuses on management of a "Fury" buff. Most of their skills build or require a certain amount of Fury (and their Ultimate skill aids in this). Fury raises the damage the user deals with each stack (it begins with a small boost to ATK and MAT), but also decreases the Soulrager's defenses and Accuracy (this gets to the point where, at the Fury stack cap, they have essentially 0 defense, Fury reducing defense by 5 in a game where before buffs you'll only ever see 5 defense if you min-max for it (weanwhile that same combination nets you only 3 attack, 0 magic attack, and 0 agility, not to mention the resource mechanic that can reduce defense even further if you're not careful in managing it (at the advantage of extra attack. At most, the resource mechanic boosts the user's attacks by 6 at the cost of lowering their defenses by another 3. Just keep in mind that enemies utilize the same resource mechanic and with at most 34 health, an extra 5+ damage per hit is huge. Though the stats do have a minimum of 0.)
...Yes. My game revolves around quick, though none-the-less strategic (hopefully. Still in early development), combat. It's kind of like Paper Mario: Thousand-Year Door, but with more thought in available choices.