Escaping the earth's gravity well is the millstone about the neck of the exploration of the rest of the Universe for the Earthling humans.
Really? I woiuld have thought, by any measure, the sheer size of the galaxy, let alone the universe, is the actual millstone. The delta v required to reach orbit (11.2 km/s) is only a quarter of the size needed to escape the gravity of the sun (42 km/s) and thus escape the solar system. Even then, you will get nowhere, the delta-v required to travel anywhere is measure in fractions of the speed of light, and any practical speed (for the purposes of travelling) is measured in units far above what we can hope to achieve. By way of example, it will take the fastest moving object we have sent to the edge of our solar system millions of years to reach the next star. The galaxy is billions of stars deep.
Clearly, then, if we want to actually explore the universe, we must find a away to do so that doesn't require physically moving a probe in the direction of interest. In which case, delta-v to orbit around earth, as challenging as that is, is generally irrelevant.