I'm sure Sigurd's debate will be...better, longer, but here goes my short rebuttal anyway.

Well, he gave us free choice, that means if we do evil, it's us not him, what you want is no free choice, but that wouldn't be perfect.
The other thing is quite silly, if he is not all-powerful and cannot make the world better, then he isn't an underachiever as it is not possible for him to make things better, or would you consider yourself an underachiever because you cannot fly when naked without any tools?