Re: Where can we live??
The answer to this actually lies in how close both the planet itself and life forms are to human life. My belief is that to accomplish this the planet would be so similar to Earth that it is not realistically possible without major atmospheric change, that would destroy the native life found there.
Humans could live on that world if the planetary conditions were similar to Earth, but that would be unlikely. We could make the planet human livable, but in the process the native life will be destroyed. As for the ethical considerations, that could only be determined by the GM. If the GM wants a game similar to the original Star Trek, then have the humans go around forcing all others to adopt human values. Or the GM could say a society that is similar to Next Gen Star Trek. In this case the society will do everything in their power to preserve all life in its original form and will not do anything other than small self contained bubbles on such planets. It is never a good idea to destroy the native life since they could teach us many things about life in general and give everyone much in the way of technology, medicine, chemistry, and every other aspect of human life.