Interesting story turned into a quest at the end!

I think maybe the best we've been able to use gravity so far, is to use its attractive force on space ships approaching a planet t sling shot it away at a faster speed as speeds up from close approach then flies off after one revolution.

Maybe someone will invent some sort of glider that is able to expand its wingspan as velocity increases. A person in such a glider or wearing a glider outfit could jump from a height and end up on a path similar to that of the downward travel of a roller coaster, or a parabola, using the downward force of gravity and the lift force of the glider wings to turn vertical velocity to horizontal speed. I'd try that! :-)