ok, I've tried no lvling on purpose once and it was kinda easy. So this will be next I guess.

How about catching chocobos, you gotta fight then right? is that allowed?

my tip if you want to make this easier is use steal to get items alot. And make your characters into class specific characters, meaning Cloud will not get any magic or summon materia cause that will screw up his strength and hp, it really helped me when I didn't lvl.