Realistically : Nothing.
I'm aware of all my flaws and I am actively working to overcome them (to the point of exhaustion some days)
Unrealistically : Everything
There's this quote from a series I've watched a long time ago that stuck with me.
“I don’t want to be human. I want to see gamma rays, I want to hear X-rays, and I want to smell dark matter. Do you see the absurdity of what I am? I can’t even express these things properly, because I have to—I have to conceptualize complex ideas in this stupid, limiting spoken language, but I know I want to reach out with something other than these prehensile paws, and feel the solar wind of a supernova flowing over me. I’m a machine, and I can know much more.
—John Cavil, Cylon Model Number One, “No Exit”
Of course this is fantasy but I'm sure there are other people out there who wish they could do more or be more.