Colors - I prefer less variation of colors in the letters. I don't mind the 4 separate colors for the symbol portion as in #4 and #5. If one letter has a standout color it should be the X, as in #5.
In #5 I think talking heads is interesting. I'd like to see what necks facing outward looks like.
#4 looks like 4 communication bubbles coming from a central location or person. Maybe it represents each item being shared with a different person or group. Overall they form an X. I'm not sure what the blue line in the E represents?
The little guy in #6 is interesting, but I'm not so sure about the communication bubble of color around it. I think the communication bubble(s) are better as an image to the side as in #4.