Any account of gratuitous evil has to avoid evils that are implied in the existence of goods, or at least implied in the existence of lesser goods. But this is a very broad class of evils and it’s hard to see how one can know that he avoids them.
First, consider that some evils are logically necessary for goods of the following type:
b.) Most sorts of heroism and bravery
d.) Retributive or corrective justice (n.b. both are goods, even as punishment)
e.) natural selection or whatever good one sees as resulting from selection (e.g. the unity of all life, the intelligibility of species, the diversity of life throughout time, the development of more complex species, etc.)
f.) Some kinds of animals (carnivores, parasites)
Other sorts of evils are statistically necessary for certain goods, i.e. while the good does not imply an evil in itself or of logical necessity, no rational person could see evils as unavoidable given the law of large numbers.
a.) Transportation by automobiles, or mass transit in general.
b.) Human wills, or simply imperfect wills.
c.) uniform laws of nature (sooner or later, gravity will cause something to fall to its death, cause the velocity of a deadly projectile, cause a hurricane that will wipe out a village, etc)
d.) Sensation (any time you have the tactile acuity of, say, a human being, at some point it will experience extreme tactile pain.)