There are things with power but no knowledge or moral will: e.g., trees. There are things with power and knowledge but no moral will: e.g., horses. There are things with all three: e.g., human beings.
These fundamental attributes mark radical qualitative differences. I suspect there are infinitely many further possible fundamental attributes besides power, knowledge and moral will. A being that had one more of these attributes would be qualitatively as far above us as we are above horses or as far as horses are above trees. But just as a horse cannot conceive of moral will, and a tree cannot conceive of anything, we cannot conceive of what these further attributes would be. All we can do is speculate that then chain power, knowledge and moral will can be continued indefinitely.
God actually has all three of power, knowledge and moral will, and has each to its maximal perfection. If my suspicion about the chain continuing ad infinitum, then all the further attributes in the chain God also has to an infinite degree. (While remaining simple.) But we have no idea what they are.