I picked Put Boots on Mars, because right now that seems more reachable.
Perhaps in the process of that, anti gravity propulsion will materialize, because we need a fast way of getting to Mars and back. If we can’t master Mars, we may not want to be venturing beyond it quiet yet...
PS. I also think terraforming Mars would be a good thing to try. To Turn that volatile red dirt and climate into a green, breathable, and sustainable, place to live would be a neat thing to do, and we would learn so much about GMO and our own elasticity.