(Not counting Personal classes) 

Unique to Aurora: (Yes there are tier 3 classes) 

Valkyrie: A Pegasus rider that can use Lances and Light magic. (Also unique to Kilva) 

Sun Knight: A mage knight that can use Light magic, Anima magic and Staffs. (Also Unique to Kilva) 

Holy Knight: A common foot soldier that can use swords or lances. (maybe even both) Can promote into a Holy Cavalier or Paladin

Holy Cavalier: Can use swords and lances (Vettel can wield Axes). Their shields can protect them from magical attacks. Can promote into a Holy Divine Paladin.

Divine Paladin: Can use swords, lances, and bows. They are effective against any type of monsters or any form of dark magic.

Solar Paladin: A promoted version of the Sun Knight. Can use Light magic, Anima Magic, Staffs and Swords, Lances, or Axes. They gain effectiveness against monsters and reduce the effectiveness of Dark magic.

Divine Valkyrie: A promoted version of the Valkyrie. Can use Swords, Lances, Light magic and staffs. They gain effectiveness against monsters and reduce the effectiveness of Dark magic.

(Might be updated) 

Unique to Kilva

Valkyrie

Divine Valkyrie

Shadow Knight: A mage knight that focus on the dark arts. Can use Dark magic, Anima magic and staffs. (Also unique to Gloria)

Sun Knight

Shadow Paladin: The promoted version of the Shadow Knight. Can use Dark magic, Anima magic, Staffs, and Swords, Lances, or Axes. They effective against Anima magic and reduce their effects. (Also unique to Gloria) 

Solar Paladin

(Might be updated)

Gloria: 

Beast Tamer: Unknown secret.

Shadow Knight

Shadow Paladin

Eagle Knights

(Might be updated) 

Cordis:

 (None for now) 

Viridi:

Eagle Knights: A Pegasus knight that uses it bow to hunt down other fliers and uses in lance to confirm the kill. (Can use Bows and Lances. They also have plus 1 movement but their resistance gets heavy nerfed, unlike Falcon Knights.) Was found in Viridi first before Gloria decides to adopt it. (think about it tier-three promotion.)