I understand that the cover itself isn't a big deal but in including artwork for a cover, it's there to draw a reader in and in some cases suggest what's going on. Bad cover art can be detrimental to a book. That being said I mostly come at this through comics so maybe novels are different though that's just how I perceive it.
I will say that I like it in theory but the framing is awkward. It looks like we're too close to the Alien and so the Alien looks huge. Maybe including an arm or zooming the scene out would be better suited. Muting the metallic color of the helmet would also help given the choice in color. The focus should be on the Alien with our eye leading to the helmet. But the helmet being too bright draws us right to it.
Though one could have just as easily done that shot from AVP where Grid lifts up Chopper and we get the hiss but instead of Chopper its a knight.