Why the other casters need buffs and Red Mage does not need a nerf.

[Frowny]

complex rotation on top of it like Blm (yes our lv70 rotation might look easy on paper but go try keeping it up in a real fight)

I wouldn't say that makes a rotation "complex", just that any mistake is punished FAR more than probably necessary. Every class needs to compensate to some degree for mechanics so ideals are always tossed aside.