Final Fantasy 3 - Class Job leveling up fast is boring, leveling up fun way is better (UPDATE)

Showing some examples of what is actually fun way of leveling up your classes in FF3 game. 3D remake, Pixel Remaster or whatever. I think guarding 5/10 times and then beating up Goblins is unrewarding, boring and just adds zero variety to time waster. Feel free to disagree though