If it ends up on Showtime, it would no doubt be more "natural" if by that you mean, without the broadcast imposed style of being sanitized and limited in the emotional impact of events (episodic style) because that is contrary to what the premium cable audience expects, even in genre shows.
Having the show be Earth based would destroy a key feature of Star Trek
, that it's different from the zillion sci fi series set on modern day Earth. The basic Gary Seven concept is very familiar on TV today, but I want a show based in space.
Rotating the characters would be good, since as has been mentioned many times, it's realistic for the military anyway.