Now I'm working on Banshee, a space-opera novel that, on a fundamental level, is about putting a human being on a ship with a whole lot of different aliens and asking, "So how is this going to work?"
There are some hard questions that can be asked that a lot of sci-fi works tend to ignore or only give a passing nod to.
If I'm being honest, on my end, I'll probably be giving a passing nod to some of them myself. But here are some things I've been thinking about in terms of putting nearly a dozen different alien species on one ship together. First and foremost, the question of, "Is this even worth the trouble?" Can the advantage of mutual cooperation amongst different species outweigh the inherent difficulties in trying to live in the same space?
Let's just presume, in this instance, that most species on the ship have a respiration cycle that requires oxygen. It's not a terrible presumption, mind you-- any respiration cycle will need a molecule that's reactive, but not TOO reactive-- but then you have the question of How Much Oxygen? Odds are not everyone will need the same balance as everyone else. What if one species needs, say, 30% oxygen in their atmosphere? Then the reactive properties that make oxygen molecules useful for humans becomes a little more problematic. What if one species requires an atmosphere that's toxic to another? What if one species's waste product is toxic to another?
How do you decide who needs to just wear an environmental suit, since their environmental needs are far too inconvenient to everyone else?
Other factors to consider, just for starters: Gravity. Light levels. Temperature tolerances. Radiation levels.
And that's just about being in the same space.
What about working in the same space? Even presuming that interspecies communication is functional enough to facilitate working together, what about ergonomics?
How do you make workstations that accommodate beings with different body sizes, body types, forms of fine-motor control, visual ranges and hearing ranges? Do you put chairs at them? If you aren't humanoid, chairs are pointless. If you have only two hands (or equivalent) then using a console designed for four or more will be very challenging. Similarly, if you have four or more, using a console designed for only two would feel woefully inefficient.
So you have to ask yourself, which compromises are the best fit for everyone, and which ones create ones that everyone can tolerate, but no one is comfortable with? And at what point would it become too hard to be worth the trouble?