1) Sensor interfaces have come a long way and to dismiss the potentially very rich virtual reality experience one could have with "looking at a computer screen" is dated and provincial. Here is just one article on upcoming developments that would allow physically walking around a virtual scene.

Virtual Reality improvements

One could further develop that to actually change elevations underfoot. Probably the most intractable issue would be simulating gravity. That could only be done from orbit (and as I have stated previously one of the few legitimate purposes for ISS would be to simulate various gravities with a centrifuge). Instead of a handful of astronauts experiencing other worlds, millions of ordinary earthbound people could through such interfaces. Space science could be funded from "virtual reality rides" of this sort exploring various worlds and environments seeded with space science probe data.

Walking in the canyons of mars or around the volcanoes of IO or diving into the lakes of Titan could be experienced as well as standing beside a "black smoker" virtually. This could be done without all the inconveniences, (tremendous) costs, and incredibly lmited numbers of people associated with a real manned visit. As robotics, sensors, processing power, virtual reality, etc. inevitable improvements occur over the next decade the case for this approach will get stronger and stronger.

2) With all the science and prospecting data from the science probes, we should set up simulated colonies here on earth to figure out how man could survive off world indefinitely within reasonable economic limits. This would ultimately produce the requirements for off world infrastructures. Life support issues are the thing that concerns me most, not ballistic delivery and far from losing the technology that technology would be accelerated by concentrating funds here on earth to do the appropriate experiments and developments. The following is a baby step on the this path. Instead of a billion dollar shuttle flight I would fund this kind of reasearch with another billion.

Life Support Pilot Plant Paves The Way To Moon And Beyond

3) Using teleoperation the required off world structures could be built and then seeded with humans. The ballistic delivery of human beings to some location is the simplist aspect of this process. Unfortuanetly, NASA will continue to do this last step prematurely, and thus unsustainably and wastefully.

We might already have a colony if we hadn't wasted 300 billion on shuttles and ISS, both of which were so obviously flawed from the beginning and almost entirely politically motivated.

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So, we need to recon and prospect to find potential colony sites. Simulate the colony on earth (relatively cheaply) to get the bugs out. Teleoperate the construction. And lastly, seed the colony with humans.