Thanks for your designs!
I like
#75 because it has a bold font, in a corporate dark blue, and it integrates a star.
#72 and #73 I also like because the DC with a star looks simple and sophisticated.
In #74 I do not want to use such a clear Pentagon shape. My clients may think that I am trying to represent myself as an employee or office of the Pentagon (which I am not) so I don't want to confuse them.
In #76 I feel like the DC is too much of a visual focus especially because it is not so easy to see that it is a D and a C.
Keep trying!