Re: Economics of reusability
"I thought the Space Shuttle demonstrated that the nice idea of reusable rockets being cheaper didn't really work with space vehicles"
You'll need a few qualifications on that statement. They would include :-
That's built to a fixed constant cost cap which took *no* account of inflation (in the 1970's).
Part of whose goal was job preservation at a series of NASA and contractor sites in various political, constituencies.
That would *force* the winner to develop a newer higher performance engine an an engine cycle they had no experience with.
With a thermal protection system driven *solely* by weight consideration and thermal capacity, not cost or replaceability.
To lift a payload 3x what NASA wanted for their internal use.
With a cross range to fly a mission it *never* attempted and which would have probably triggered WWIII if it had.
Under NASA's micro management culture with the *complete* authority to demand tear down and redesign if *any* thing did note meet with their complete approval.
You might like to consider what sort of vehicle you could come up with that set of constraints.