Supernaut - How to cheat at Space Exploration
Supernaut is functionally free Delta-V with a brain.
He can easily go anywhere in the solar system without any additional equipment and carry a payload with him, that's fantastic in every sense of the word.
The best thing Supernaut can do is learn the engineering requirements to maintain space hardware so he can just go out and deal with ad-hoc problems without a multi-billion dollar expedition.
Even without specialist knowledge, our super-astronaut provides the incredible service of being able to physically go fetch defunct or damaged satellites and bring them home for repairs before putting them back.
If you're not keeping him busy with big projects, Supernaut can easily go land instruments and equipment on practically every body in the solar system, you want to know what that bright shiny spot on Ceres really is? He can go fetch a sample of the water-ice there and bring it back for your coffee.
He can physically carry a box containing a mars rover, set it on the martian soil, open it and leave again. No more huge rockets for tiny payloads.
Cubesats? He can carry a crate of them and deploy them anywhere in the solar system for free.
Supernaut can very easily go prospecting for useful minerals and bring back samples so you can decide whether mining there is worthwhile too.
Supernaut's spare time can be filled accelerating fuel and cargo pods into Hohmann trajectories to resupply missions throughout the solar system. Essentially free Launch Delta-V means that they can simply carry enough to perform their deceleration at the other end and rendezvous with whatever they're there for.
What about Asteroid mining?
With the savings on the smaller missions, nearly all the budget can go into the construction of a modular mining spacecraft which Supernaut can carry in sections and help assemble in orbit.
The actual flight to the asteroid can be conducted conventionally with the ship running uncrewed on automatic, our Supernaut can then ferry the crew in a small car-sized passenger module and take far far less time to do it.
This negates most of the challenges of keeping a crew alive for the months it might otherwise take to get to the asteroids.
Remember that Supernaut can be under power continuously the whole time, a week at most to rendezvous with the mining ship in a craft comparable to the Apollo Orbiter is pretty acceptable.
If sending a crew to mine asteroids doesn't appeal though, you can still have Supernaut ferry boosters out to the target asteroid so it can be pushed into a more accessible orbit remotely. Having Supernaut do the pushing will be long and tedious compared to setting up something more slow-burn and leaving it alone.
Asking Supernaut to physically mine or even to fetch asteroids would be a staggering waste of potential.
Really your only concerns as NASA Administrator is in keeping Supernaut happy and busy. Pay him whatever he asks, because it's bound to be cheaper than doing things conventionally.