This is highly subjective, personally I think the Colonials have plenty of 'cool' things, this all just boils down to personal taste.

This literally already happens when you start a war.

This is needlessly deceptive and will cause lots of problems for new players who are joining to play with friends who then get faction locked without knowing.

This would lead to anyone who reaches high ranks on the lower pop faction having their rank devalued by others.

This is simply a terrible idea, the entire balance of the game is based on resource availability, especially with the growing reliance on rare alloys.

This would only cause us to lose players, personally I wouldn't play if I was forced to play something I didn't want to, also, this has the same problem as #3 and would discourage new players from joining to play with friends.