Adjustment of Status - I-485

So, like some of you may have heard, there are news report that the Trump administration is trying to expand the travel ban to include 7 more countries. My country Nigeria is said to be part of the additional countries.

I am already a green card holder, but I am concerned this may affect green card holders traveling and returning freely. I want to find out from any of the countries currently on the travel ban: Iran, Syria etc, do the green card holders from these countries face any issues/additional scrutiny at the port of entry? I am asking because I already paid for a cruise this March, but concerned I may face additionally scrutiny if Nigeria is indeed put in the travel ban list before March. Is there anyone you know from the countries currently banned who has a green card and has traveled recently? Did they face any issue while returning?

Also, how has the travel ban affected citizenship processing of people from these countries? In other words, does a travel ban of a particular country affect citizenship applications of people from that country?

Thanks.