Interesting thread. I grew up and live nearby. I went on a school trip in like 3rd grade and I went on another tour when we had family in town. I always thought it was boring as fuck and I was always more interested in the tourist trap stores nearby.
In 2006 I went to a concert on the queen mary called Float the Boat. pic related. It was a really fun night.
Not long after that is when TWIC came out. The main TWIC office was in some shitty building down by the queen mary. I remember the submarine but I cant remember if I actually went in it or if I just walked though some small museum area. I do remember russian music being played.
I say scuttle the queen mary and the submarine. Make them diving attractions.