We had wanted to do the cable car and I'm glad we did but I really wouldn't rush to see it.
It's a short trip and it takes you to the dome do we just got back on so we could get back on the DLR and connect elsewhere.
I find the queuing system a bit ridiculous. We wanted a round trip but because we hadn't paid for the 'experience' ticket, we had to get of, walk downstairs & back up again instead of being allowed to stay on & let the oyster system charge us for a return trip when we left. Was just an irritation which could be avoided.
The views were lovely and you could see the London City airport landing strip. I really don't get why you gave a TV in each pod with quite a loud video playing though - it just distracts from the views and is unnecessary.