theres always a way around the "you cant wish for that" rule. for instance, no matter what the rules of the eternal dragons wishes are, you can preconceive a fictional object that WILL give you infinite wishes, or at least a very similar level of power over reality, and wish for that. like, "i wish for a pill that when i swallow it, it will grant me the ability to make my imagination control reality." this object can actually be much more complex, which can be extremely important considering that any ambiguity in ones wish can have serious unforeseen side-effects. for example, i said "control reality" if id said "affect reality" the phrase could be interpreted to be not much different than how i already am. in the world of dragonball z, i would say that perhaps the best possible wish is "grant me power more than nine thousand."