I suppose one of my problems is that I have trouble with the idea of a spacecraft as a commercial vessel. Commercial space travel (and by that I mean moving
people for money) may be
very close but as yet it is still a future thing. The first customers will probably be governments anyway, and if they see it making a profit they'll try to take it over and ruin it in the process. Government run missions are still feasible if you can convince the PTBs that it might be
politically profitable for them, but then they will insist on having some input to the mission design process (which frankly scares me a bit). Now I be overreacting to having re-read "2001: A Space Odyssey" recently but until I see some serious advertisements for tickets on a spacecraft at
affordable prices I will regard the whole topic as "maybe someday" speculation.
At the moment my spacecraft design is mission oriented with cost something to be considered by the bean counters back home. And in this case the "mission" is primarily political; settle Mars. The tools might not be absolutely efficient but they will (hopefully)
look good to the people whose support the politicians want. Sorry to be such a downer, but we are living in a political time and politics seems to be all I hear about on the news any more. :(
Dalton “So let's pretend we can actually do this” Spence