Writer's Block: No regrets
I myself would like to remove the emotion/feeling of SADNESS. Of course, everyone would like to do so if given a chance. Don't people long for happy moments? Don't they curse their luck for bringing grief to them?
I myself would have taken an eraser and wiped out the emotions called "SADNESS, PAIN" out of the diaries of this world so that mankind would have survived happily but, for the survival of mankind the elimination of Sadness, pain aren’t the only factors...
That would have worked wonders, eh?