You can treat your PPT as an interesting format to give them an idea about your extras. Try to make it like a good PPT, meaning interesting and using bullets. Dont write 4 more pages of essays for a ppt.
You definitely can work extras into your essay 1, just dont throw it it in there. You need to make sure it fits and flows. Also you can always pick a person related to your extras to write about in essay #2, so that you can get in more info that way. I feel that Essay #2 is going to be typically underutilized by applicants...it isnt a report on a person you admire, its another opportunity to let the adcoms know more about who you are and what you believe beyond a resume and the 1500 word essay.
GMAT gets a spot and has value but dont overestimate it.