I wouldn't know how to nerf certain jobs but buffing I have some ideas.

Red Mage
Increase the damage buff duration from Manafication from 10s to 15s or 20s. At the current moment when you use manafiction for the first few seconds of the buff you are doing your melee combo not gaining any of the benefit from the buff.
Corps-a-corp should have 2 charges.
Displacement and Engagment should possibly have 2 charges as well but atm not sure.
Enchanted melee combo should be buffed. Enchaged Riposte should be as strong as Jolt 2 with a potency of 250. Zwerchhau should be 330.
Embolden should buff all dps and not just melee dps.

That's all I have.