Fabulous question CloudExplorer!
Their would first be quality food and health care for all living species, especially humans.
My second priority would be to change the educational systems by implementing, at the earliest possible levels, the following courses:
1) The Definition of Love
2) The Art of Gratitude
3) The Gift of Forgiveness
4) The Reason for Collaboration
5) Self Examination and the Impact of the Ego
6) Understanding Your Callings and The Act of Co-Creation
7) The Power of Peace (including mandatory peace rallies)
There would be remedial study for slower learners and accelerated classes for those with the desire to help teach others.
Everyone would have a mentor and a coach to help them obtain their goals, providing the outcome of those goals was for the highest good of all concerned.
After this I would enroll myself as the first student. Then I would share the idea that everyone already possesses all they need to change the world and they can start immediately. All they had to do was to choose to begin by surrendering themselves, asking for whatever help they needed, and taking the first step forward.
Then I would throw the biggest celebration the world had ever seen!
There's more, but I'm currently overwhelmed with gladness for having contributed so much with so little! (Gentle Chuckle!)