No offense to the great Patricia Tallman, the fantastic actor and stunt person largely known for her work on Babylon 5 as well as the 1990 remake of Night of the Living Dead. The wide eyes just seemed an odd choice.
My DS9 is rusty, but I think most people were expecting it to fail or go boom. So the portrayal here might have been meant as a "huh, we didn't blow up" type of reaction.
If they raised a kid together, we’d have a one-person trek series with a few extras but all the main cast is just their power concentrated into one acting god.
Not an extra, extras don't have lines, they are just animate props whose photos were picked from a pile. This is a bit part played by a real actor who auditioned.