The dorsal appendages are out of proportion but the illustration is awesome.
Ive often thought about how the dorsal appendages would affect the Alien in a fight. Firstly, the lengthy head gives a lot of leverage to twist the alien's neck. Secondly, the minute the alien tilts his head, he's stuck on the central dorsal fin, or even unable to turn his head.
Sooo.... for me, it's basically one uppercut, and then I reach around to grab the back of the head and keep it stuck among the dorsal arrangement. Got him!
Arrgh! The tail! Between my legs! Owww!