You guys obviously don't realize how to do all those things you want to do.
Yes DBZ's signature ability Ki.
and also the master sword for time travel.
Although you could do all that by being a super genius but who needs that
The ability to either control time, persuade people to do whatever I want with out brainwashing them, or teleporting. The smartest option I believe is being able to teleport and being able to teleport others with you. Nothing could hurt you. Ever.
Without a doubt, I would choose the ability to manipulate time in any and every way possible. This include going back, going forward, slowing down, speeding up, freezing it, anything. I feel like one can easily become the ruler of all superhumans because of all the knowledge obtained in the future and applying it in the present.
When I was little, I always wanted to have the ability to fly, I also wanted to have elemental abilitys. But if I had to narrow it down to three, I'd choose fire, ice, and electricity. Being able to talk to animals would be cool, but, well, not offensive enough to enemys. I like powers that can defend your friends or attack bad guys.