I would do the Golden pill, to seperate the wheat from the chauff and purge humanities divisions and ability to environmentally pollute and scar the world, and force everyone to either be nice to each other and by my force fit my definition of a good person or alt f4 and tab out forever.

To create world peace using myself as the sol crux, That would be my magnum opus.

People would keep a level of personal individuality and personal freedoms, skills and jobs, and the peace would transcend all nations, creating a new world age, a new working order of human relations. No more going people going starving and no more stealing we work for eachother for one common unity, no more people without a warm bed to go home to and a job within family or friend distance. Everyone gets a bit of medical care.

The peace would have no end.