I'm obviously not the writer, but I'm certain Connor has those eyes for a reason. Ronan has dark brown eyes that turn amber-colored when riled up or in wolf form. With just a simple google search, you can learn that Amber eyes "symbolize the radiant embrace of love". This definitely holds true to his character, and the inability he has to move on from Nick. Connor theorizes that it's because of his wolfy feelings, seeing Nick as a lifelong mate. That makes it all the better that his glowing amber eyes show up only when his werewolf instincts are tapped into. Blue eyes are known to symbolize wisdom and knowledge, which I'd say fits Connor very well. He can be the first person to open up about this world to Alex honestly, he has a go with-the-flow vibe, and it's obvious he knows a lot about Elders and their world due to his own life. His eyes are most likely unnaturally shaded to make him stick out. They have a very ethereal vibe that instantly tells the viewer he's not of this world.