I'll agree on the writing of characters. XO Kendal and the Shepherd character need a shot in the arm or something because they are bland and bland.
The French NATO girl, I'm still confused by her presence besides being a "War is bad" person. The XO is married, Chaplin has at least 25 years on her, special forces guy has the bar maiden, so she isn't a romantic subplot in waiting. So what is her point now? Hopefully it's not to just blithely come to agree with the crew.
I really hope this show does not go the route of Lost in the long run, becoming so burdened with mystery and it's own mythology that it becomes crushed under it. They need to solve some mysteries while adding intrigue later on.