I remember sensory things, like the audio, the cool air blowing on the window so it wouldn't get foggy, peering out into the darkness, fun stuff. But I can understand why it was not improved. Too difficult getting into the subs (ADA issues), tiny seats and the queue wasn't anything special. I can only imagine what some advanced underwater AAs would have been like if they had decided to do a refurb; that could have been really neat.