This is amazing. You have a great eye for details. So many things catch my attention when looking at it. For example I really really like your facial expressions. Also their posture; the way you drew them standing plus their facial expressions just makes them seem so real. Basically I love this and I think you did a freaking amazing job with it.
Thanks very much! I try to keep it interesting by not repeating poses and compositions too often, and changing up the coloring so the covers don't all feel the same. Dark horse generally doesn't want really extreme facial expressions on the characters'/actors' faces, but I use as many variations as possible in the narrower band I'm working within.