Assume it's possible (economically, politically, scientifically) to send a limited number of volunteers on a "one-way" scientific & exploration mission to another planet, like Mars.
- What would a "one-way" crew look like? All male? All female? A mixture? A mixed crew would certainly allow the story to get interesting.
- What is the composition of the "sending agency"? A single country? A consortium? A business or group of businesses? It might be more interesting if there was some capitalistic reason to make the trip, for example "We, the XYZ Corporation, claim Mars as our own", or perhaps the discovery (by an automated probe sent to Mars) of some extremely valuable substance. This, of course, would require a working probe (ahem), which seems to be beyond the reach of the best JPL scientists. And the existance of this Martian substance doesn't do the people of Earth any good unless the substance can be returned to Earth, which implies a way to return, which invalidates the entire "one-way" concept of the story. And the whole "rare substance" thing probably sounds too much like "Dune"
- What sacrifices have been made by the "sending agency" to make this trip possible? Any resentments there? Did they go with lowest bidder (guaranteed to build almost working components - use & enjoy!).
- What would be the motivation of the members? Greed? Scientific curiosity? Altruism? What if their families back on Earth were guaranteed a comfortable (or even opulent) existance for, let's say, 100 years?
- Are the crew members comfortable with the possibility that this may be a suicide mission? Anyone in denial about that?
- What would happen on the voyage there? Boredom? Danger? Sickness? Sex?
- What if, during the voyage, one of the crew has a spiritual or religious experience/awakening, and decides that suicide, or even the possibility of suicide, is not compatable with their new belief system? The person would demand to be rescued, and the sending agency would counter with "you signed this contract, bucko". This would obviously lead to anger and depression. Anything else? Revolt? Sabotage? Threatening the mission or other crew members ? Would their family back on Earth play a part, perhaps as hostages? This person would eventually be forced to settle down and accept their fate, because their anger is what's going to fuel their survival once on Mars.
- On Mars, what are the difficulties with the necessities (food, water, shelter)? Can any of these be provided by the planet? Do we want any mysteries, like the discovery of some object which is obviously artifically created? How about life-saving conditions like sub-surface water? Would the person who finds it share it with the others?
- Is this sounding a bit too much like "Contact" or "Robinson Crusoe on Mars"?? Damn. I hate it when that happens.