Sometimes I miss some family members or friends that could be enjoying the trip with me. I find myself saying that "so and so would really like this or that."
I also miss the comfortable stadium seats that are in many movie theaters now. On some ships, large screen movies are presented in the smaller lounges in those uncomfortable or too comfortable lounge seats or boothes. The low back of the small seat in the lounge was too uncomfortable and I fell asleep twice when I made myself too comfortable in the semi-circle lounge booth. Could it have been the movie?
Other than those two things there's not much that I miss. I'm usually too busy on the ship to miss anything else.